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Bard E, Miramont C, Capano M, Guibal F, Marschal C, Rostek F, Tuna T, Fagault Y, Heaton TJ. A radiocarbon spike at 14 300 cal yr BP in subfossil trees provides the impulse response function of the global carbon cycle during the Late Glacial. Philos Trans A Math Phys Eng Sci 2023; 381:20220206. [PMID: 37807686 PMCID: PMC10586540 DOI: 10.1098/rsta.2022.0206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 03/06/2023] [Indexed: 10/10/2023]
Abstract
We present new 14C results measured on subfossil Scots Pines recovered in the eroded banks of the Drouzet watercourse in the Southern French Alps. About 400 new 14C ages have been analysed on 15 trees sampled at annual resolution. The resulting Δ14C record exhibits an abrupt spike occurring in a single year at 14 300-14 299 cal yr BP and a century-long event between 14 and 13.9 cal kyr BP. In order to identify the causes of these events, we compare the Drouzet Δ14C record with simulations of Δ14C based on the 10Be record in Greenland ice used as an input of a carbon cycle model. The correspondence with 10Be anomalies allows us to propose the 14.3 cal kyr BP event as a solar energetic particle event. By contrast, the 14 cal kyr BP event lasted about a century and is most probably a common Maunder-type solar minimum linked to the modulation of galactic cosmic particles by the heliomagnetic field. We also discuss and speculate about the synchroneity and the possible causes of the 14 cal kyr BP event with the brief cold phase called Older Dryas, which separates the Bølling and Allerød millennium-long warm phases of the Late Glacial period. This article is part of the Theo Murphy meeting issue 'Radiocarbon in the Anthropocene'.
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Affiliation(s)
- Edouard Bard
- CEREGE, Aix-Marseille University, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, BP 80, 13545 Aix-en-Provence, France
| | - Cécile Miramont
- IMBE, Aix-Marseille University, CNRS, IRD, Avignon University, Technopôle de l'Arbois, 13545 Aix-en-Provence, France
| | - Manuela Capano
- CEREGE, Aix-Marseille University, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, BP 80, 13545 Aix-en-Provence, France
| | - Frédéric Guibal
- IMBE, Aix-Marseille University, CNRS, IRD, Avignon University, Technopôle de l'Arbois, 13545 Aix-en-Provence, France
| | - Christian Marschal
- IMBE, Aix-Marseille University, CNRS, IRD, Avignon University, Technopôle de l'Arbois, 13545 Aix-en-Provence, France
| | - Frauke Rostek
- CEREGE, Aix-Marseille University, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, BP 80, 13545 Aix-en-Provence, France
| | - Thibaut Tuna
- CEREGE, Aix-Marseille University, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, BP 80, 13545 Aix-en-Provence, France
| | - Yoann Fagault
- CEREGE, Aix-Marseille University, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, BP 80, 13545 Aix-en-Provence, France
| | - Timothy J. Heaton
- Department of Statistics, School of Mathematics, University of Leeds, Leeds LS2 9JT, UK
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Gao X, Zhao B, Chen Z, Song W, Li Z, Wang X. The Impact of Urbanization on Tree Growth and Xylem Anatomical Characteristics. Biology (Basel) 2023; 12:1373. [PMID: 37997972 PMCID: PMC10669791 DOI: 10.3390/biology12111373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/21/2023] [Accepted: 10/23/2023] [Indexed: 11/25/2023]
Abstract
In the context of the intensification of global urbanization, how urbanization (urban heat island effect and air pollution) affects urban tree growth is not fully understood. In this paper, the radial growth and xylem anatomical characteristics of three different tree species (Quercus mongolica, Fraxinus mandshurica, and Pinus sylvestris var. mongolica) in urban and rural areas of Harbin were compared by means of tree-ring anatomy. The results showed that there were significant differences in the growth of both broadleaf trees and conifers between urban and rural areas. The vessel number, cumulative area of vessels, and theoretical hydraulic conductivity of all tree species in rural areas were higher than those in urban areas, indicating that urbanization may have the effect of slowing down growth. However, broadleaf trees in urban areas had higher vessel density and a greater percentage of a conductive area within xylem and theoretical xylem-specific hydraulic conductivity. The thickness of cell walls and cell wall reinforcement index of P. sylvestris var. mongolica were strongly reduced by air pollution, implying that it may be more sensitive to urbanization. Compared to Q. mongolica, F. mandshurica showed less sensitivity to urbanization. Warming and drying climate in Harbin may be an important factor affecting tree growth.
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Affiliation(s)
- Xiaohui Gao
- Aulin College, Northeast Forestry University, Harbin 150040, China
| | - Binqing Zhao
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Zecheng Chen
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Wenqi Song
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Zongshan Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xiaochun Wang
- Aulin College, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin 150040, China
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Watanabe Y, Yamagishi S, Takata N, Tsuyama T, Yasue K, Ohno Y. Formation of xylem tissues and secondary cell walls is diminished by severe and consecutive insect defoliation. Am J Bot 2023; 110:e16232. [PMID: 37661818 DOI: 10.1002/ajb2.16232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 09/05/2023]
Abstract
PREMISE Insect defoliation of trees causes unusual changes to wood anatomy and slows radial growth that decreases tree value; however, the characteristics of these anatomical changes in hardwoods remain unclear. The aim of this study was to characterize the anatomy and histochemistry of the wood in trunks of Betula maximowicziana trees after severe insect defoliation. METHODS Secondary xylem tissues were sampled from trunks that had been defoliated by Caligula japonica at Naie and Furano in central Hokkaido during 2006-2012, then cross-dated and examined microscopically and stained histochemically to characterize anatomical and chemical changes in the cells. RESULTS White rings with thin-walled wood fibers and greatly reduced annual ring width in the subsequent year were observed in samples from both sites. From these results, the year that the white rings formed was determined, and severe defoliation was confirmed to trigger white ring formation. The characteristics may prove useful to detect the formation year of white rings. Scanning electron microscopy and histochemical analyses of the white rings indicated that the thickness of the S2 layer in the wall of wood fiber cells decreased, but xylan and lignin were still deposited in the cell walls of wood fibers. However, the walls of the fibers rethickened after the defoliation. CONCLUSIONS Our results suggest that B. maximowicziana responds to a temporary lack of carbon inputs due to insect defoliation by regulating the thickness of the S2 layer of the cell wall of wood fibers. For B. maximowicziana, insect defoliation late in the growing season has serious deleterious effects on wood formation and radial growth.
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Affiliation(s)
- Yoko Watanabe
- Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Shohei Yamagishi
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
- Forestry and Forest Products Research Institute, Tsukuba, 305-8687, Japan
| | - Naoki Takata
- Forest Bio-Research Center, Forestry and Forest Products Research Institute, Hitachi, 319-1301, Japan
| | - Taku Tsuyama
- Faculty of Agriculture, University of Miyazaki, Miyazaki, 889-2192, Japan
| | - Koh Yasue
- Institute for Mountain Science, Shinshu University, Minami-minowa, 399-4598, Japan
| | - Yasuyuki Ohno
- Forest Research Institute, Hokkaido Research Organization, Bibai, 079-0198, Japan
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Dechaine AC, Pfeiffer DG, Kuhar TP, Salom SM, Leskey TC, McIntyre KC, Walsh B, Speer JH. Dendrochronology reveals different effects among host tree species from feeding by Lycorma delicatula (White). Front Insect Sci 2023; 3:1137082. [PMID: 38469497 PMCID: PMC10926496 DOI: 10.3389/finsc.2023.1137082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 08/10/2023] [Indexed: 03/13/2024]
Abstract
The spotted lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoridae), was first detected in the United States in Berks County, Pennsylvania, in 2014. Native to China, this phloem-feeding planthopper threatens agricultural, ornamental, nursery, and timber industries in its invaded range through quarantine restrictions on shipments, as well as impacts on plants themselves. The long-term impacts of L. delicatula feeding on tree species have not been well studied in North America. Using standard dendrochronological methods on cores taken from trees with differing levels of L. delicatula infestation and systemic insecticidal control, we quantified the impact of L. delicatula feeding on the annual growth of four tree species in Pennsylvania: Ailanthus altissima, Juglans nigra, Liriodendron tulipifera, and Acer rubrum. The results suggest that L. delicatula feeding is associated with the diminished growth of A. altissima, but no change was observed in any other tree species tested. The results also suggest that systemic insecticides mitigate the impact of L. delicatula feeding on A. altissima growth.
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Affiliation(s)
- Andrew C. Dechaine
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Douglas G. Pfeiffer
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Thomas P. Kuhar
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Scott M. Salom
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Tracy C. Leskey
- Appalachian Fruit Research Station, United States Department of Agriculture - Agricultural Research Service (USDA—ARS), Kearneysville, WV, United States
| | - Kelly C. McIntyre
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Brian Walsh
- Pennsylvania State University Extension, Leesport, PA, United States
| | - James H. Speer
- Geography and Geology Department of Earth and Environmental Systems, Indiana State University, Terre Haute, IN, United States
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Dudney J, Latimer AM, van Mantgem P, Zald H, Willing CE, Nesmith JCB, Cribbs J, Milano E. The energy-water limitation threshold explains divergent drought responses in tree growth, needle length, and stable isotope ratios. Glob Chang Biol 2023; 29:4368-4382. [PMID: 37089078 DOI: 10.1111/gcb.16740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 02/08/2023] [Accepted: 03/16/2023] [Indexed: 05/03/2023]
Abstract
Predicted increases in extreme droughts will likely cause major shifts in carbon sequestration and forest composition. Although growth declines during drought are widely documented, an increasing number of studies have reported both positive and negative responses to the same drought. These divergent growth patterns may reflect thresholds (i.e., nonlinear responses) promoted by changes in the dominant climatic constraints on tree growth. Here we tested whether stemwood growth exhibited linear or nonlinear responses to temperature and precipitation and whether stemwood growth thresholds co-occurred with multiple thresholds in source and sink processes that limit tree growth. We extracted 772 tree cores, 1398 needle length records, and 1075 stable isotope samples from 27 sites across whitebark pine's (Pinus albicaulis Engelm.) climatic niche in the Sierra Nevada. Our results indicated that a temperature threshold in stemwood growth occurred at 8.4°C (7.12-9.51°C; estimated using fall-spring maximum temperature). This threshold was significantly correlated with thresholds in foliar growth, as well as carbon (δ13 C) and nitrogen (δ15 N) stable isotope ratios, that emerged during drought. These co-occurring thresholds reflected the transition between energy- and water-limited tree growth (i.e., the E-W limitation threshold). This transition likely mediated carbon and nutrient cycling, as well as important differences in growth-defense trade-offs and drought adaptations. Furthermore, whitebark pine growing in energy-limited regions may continue to experience elevated growth in response to climate change. The positive effect of warming, however, may be offset by growth declines in water-limited regions, threatening the long-term sustainability of the recently listed whitebark pine species in the Sierra Nevada.
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Affiliation(s)
- Joan Dudney
- Environmental Studies Program, Santa Barbara, California, USA
- Bren School of Environmental Science & Management, UC Santa Barbara, Santa Barbara, California, USA
| | - Andrew M Latimer
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Phillip van Mantgem
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
| | - Harold Zald
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon, USA
| | - Claire E Willing
- Department of Biology, Stanford University, Stanford, California, USA
- School of Environmental and Forest Sciences, University of Washington, Seattle, Washington, USA
| | | | - Jennifer Cribbs
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Elizabeth Milano
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
- USDA Forest Service, Rocky Mountain Research Station, Moscow, Idaho, USA
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Yin T, Zhai Y, Zhang Y, Yang W, Dong J, Liu X, Fan P, You C, Yu L, Gao Q, Wang H, Zheng P, Wang R. Impacts of climate change and human activities on vegetation coverage variation in mountainous and hilly areas in Central South of Shandong Province based on tree-ring. Front Plant Sci 2023; 14:1158221. [PMID: 37342129 PMCID: PMC10277696 DOI: 10.3389/fpls.2023.1158221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 05/09/2023] [Indexed: 06/22/2023]
Abstract
Introduction It is of great significance to understand the characteristics and influencing factors of vegetation coverage variation in the warm temperate zone. As a typical region of the warm temperate zone in eastern China, the mountainous and hilly region in central-south Shandong Province has fragile ecological environment and soil erosion problem. Studying on vegetation dynamics and its influencing factors in this region will help to better understand the relationship between climate change and vegetation cover change in the warm temperate zone of eastern China, and the influence of human activities on vegetation cover dynamics. Methods Based on dendrochronology, a standard tree-ring width chronology was established in the mountainous and hilly region of central-south Shandong Province, and the vegetation coverage from 1905 to 2020 was reconstructed to reveal the dynamic change characteristics of vegetation cover in this region. Secondly, the influence of climate factors and human activities on the dynamic change of vegetation cover was discussed through correlation analysis and residual analysis. Results and discussion In the reconstructed sequence, 23 years had high vegetation coverage and 15 years had low vegetation coverage. After low-pass filtering, the vegetation coverage of 1911-1913, 1945-1951, 1958-1962, 1994-1996, and 2007-2011 was relatively high, while the vegetation coverage of 1925-1927, 1936-1942, 2001-2003, and 2019-2020 was relatively low. Although precipitation determined the variation of vegetation coverage in this study area, the impacts of human activities on the change of vegetation coverage in the past decades cannot be ignored. With the development of social economy and the acceleration of urbanization, the vegetation coverage declined. Since the beginning of the 21st century, ecological projects such as Grain-for-Green have increased the vegetation coverage.
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Affiliation(s)
- Tingting Yin
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Yinuo Zhai
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Yan Zhang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Wenjun Yang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Jinbin Dong
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Huankeyuan Environmental Testing Co., Ltd., Jinan, China
| | - Xiao Liu
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Peixian Fan
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Chao You
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Linqian Yu
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Qun Gao
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Hui Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Peiming Zheng
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
| | - Renqing Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
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Kozák D, Svitok M, Zemlerová V, Mikoláš M, Lachat T, Larrieu L, Paillet Y, Buechling A, Bače R, Keeton WS, Vítková L, Begovič K, Čada V, Dušátko M, Ferenčík M, Frankovič M, Gloor R, Hofmeister J, Janda P, Kameniar O, Kníř T, Majdanová L, Mejstřík M, Pavlin J, Ralhan D, Rodrigo R, Roibu CC, Synek M, Vostarek O, Svoboda M. Importance of conserving large and old trees to continuity of tree-related microhabitats. Conserv Biol 2023; 37:e14066. [PMID: 36751977 DOI: 10.1111/cobi.14066] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 10/19/2022] [Accepted: 11/15/2022] [Indexed: 05/30/2023]
Abstract
Protecting structural features, such as tree-related microhabitats (TreMs), is a cost-effective tool crucial for biodiversity conservation applicable to large forested landscapes. Although the development of TreMs is influenced by tree diameter, species, and vitality, the relationships between tree age and TreM profile remain poorly understood. Using a tree-ring-based approach and a large data set of 8038 trees, we modeled the effects of tree age, diameter, and site characteristics on TreM richness and occurrence across some of the most intact primary temperate forests in Europe, including mixed beech and spruce forests. We observed an overall increase in TreM richness on old and large trees in both forest types. The occurrence of specific TreM groups was variably related to tree age and diameter, but some TreM groups (e.g., epiphytes) had a stronger positive relationship with tree species and elevation. Although many TreM groups were positively associated with tree age and diameter, only two TreM groups in spruce stands reacted exclusively to tree age (insect galleries and exposed sapwood) without responding to diameter. Thus, the retention of trees for conservation purposes based on tree diameter appears to be a generally feasible approach with a rather low risk of underrepresentation of TreMs. Because greater tree age and diameter positively affected TreM development, placing a greater emphasis on conserving large trees and allowing them to reach older ages, for example, through the establishment of conservation reserves, would better maintain the continuity of TreM resource and associated biodiversity. However, this approach may be difficult due to the widespread intensification of forest management and global climate change.
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Affiliation(s)
- Daniel Kozák
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Marek Svitok
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
- Department of Biology and General Ecology, Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, Zvolen, Slovakia
| | - Veronika Zemlerová
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Martin Mikoláš
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Thibault Lachat
- Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences HAFL, Zollikofen & Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Laurent Larrieu
- Université de Toulouse, INRAE, UMR DYNAFOR, Castanet-Tolosan, France & CNPF-CRPF Occitanie, Tarbes, France
| | - Yoan Paillet
- Univ. Grenoble Alpes, INRAE, UR Lessem, Lessem, France
| | - Arne Buechling
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Radek Bače
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - William S Keeton
- University of Vermont, Rubenstein School of Environment and Natural Resources, Burlington, Vermont, USA
| | - Lucie Vítková
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Krešimir Begovič
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Vojtěch Čada
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Martin Dušátko
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Matej Ferenčík
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Michal Frankovič
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Rhiannon Gloor
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Jeňýk Hofmeister
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Pavel Janda
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Ondrej Kameniar
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Tomáš Kníř
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Linda Majdanová
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Marek Mejstřík
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Jakob Pavlin
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Dheeraj Ralhan
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Ruffy Rodrigo
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Catalin-Constantin Roibu
- Forest Biometrics Laboratory-Faculty of Forestry, 'Stefan cel Mare' University of Suceava, Suceava, Romania
| | - Michal Synek
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Ondřej Vostarek
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Miroslav Svoboda
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic
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8
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van Mantgem PJ, Milano ER, Dudney J, Nesmith JCB, Vandergast AG, Zald HSJ. Growth, drought response, and climate-associated genomic structure in whitebark pine in the Sierra Nevada of California. Ecol Evol 2023; 13:e10072. [PMID: 37206686 PMCID: PMC10191741 DOI: 10.1002/ece3.10072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 04/19/2023] [Accepted: 04/26/2023] [Indexed: 05/21/2023] Open
Abstract
Whitebark pine (Pinus albicaulis Engelm.) has experienced rapid population declines and is listed as threatened under the Endangered Species Act in the United States. Whitebark pine in the Sierra Nevada of California represents the southernmost end of the species' distribution and, like other portions of its range, faces threats from an introduced pathogen, native bark beetles, and a rapidly warming climate. Beyond these chronic stressors, there is also concern about how this species will respond to acute stressors, such as drought. We present patterns of stem growth from 766 large (average diameter at breast height >25 cm), disease-free whitebark pine across the Sierra Nevada before and during a recent period of drought. We contextualize growth patterns using population genomic diversity and structure from a subset of 327 trees. Sampled whitebark pine generally had positive to neutral stem growth trends from 1970 to 2011, which was positively correlated with minimum temperature and precipitation. Indices of stem growth during drought years (2012 to 2015) relative to a predrought interval were mostly positive to neutral at our sampled sites. Individual tree growth response phenotypes appeared to be linked to genotypic variation in climate-associated loci, suggesting that some genotypes can take better advantage of local climatic conditions than others. We speculate that reduced snowpack during the 2012 to 2015 drought years may have lengthened the growing season while retaining sufficient moisture to maintain growth at most study sites. Growth responses may differ under future warming, however, particularly if drought severity increases and modifies interactions with pests and pathogens.
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Affiliation(s)
| | - Elizabeth R. Milano
- U.S. Geological SurveyWestern Ecological Research CenterSan DiegoCaliforniaUSA
- Present address:
USDA Forest ServiceRocky Mountain Research StationMoscowIdahoUSA
| | - Joan Dudney
- Environmental Studies ProgramUC Santa BarbaraSanta BarbaraCaliforniaUSA
- Department of Environmental Science, Policy, & ManagementUC BerkeleyBerkeleyCaliforniaUSA
- Department of Plant SciencesUniversity of CaliforniaDavisCaliforniaUSA
| | | | - Amy G. Vandergast
- U.S. Geological SurveyWestern Ecological Research CenterSan DiegoCaliforniaUSA
| | - Harold S. J. Zald
- USDA Forest ServicePacific Northwest Research StationCorvallisOregonUSA
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9
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García-González I, Souto-Herrero M. Earlywood Anatomy Highlights the Prevalent Role of Winter Conditions on Radial Growth of Oak at Its Distribution Boundary in NW Iberia. Plants (Basel) 2023; 12:1185. [PMID: 36904045 PMCID: PMC10007082 DOI: 10.3390/plants12051185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/16/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
We compared climate-growth relationships (1956-2013) of two natural pedunculate oak (Quercus robur L.) stands with different water-holding capacities growing at the species distribution limit of the Mediterranean Region in NW Iberia. For this, tree-ring chronologies of earlywood vessel size (separating the first row from the other vessels) and latewood width were obtained. Earlywood traits were coupled to conditions during dormancy, whereby an elevated winter temperature appears to induce a high consumption of carbohydrates, resulting in smaller vessels. This effect was reinforced by waterlogging at the wettest site, whose correlation to winter precipitation was strongly negative. Soil water regimes caused differences between vessel rows, since all earlywood vessels were controlled by winter conditions at the wettest site, but only the first row at the driest one; radial increment was related to water availability during the previous rather than the current season. This confirms our initial hypothesis that oak trees near their southern distribution boundary adopt a conservative strategy, prioritizing reserve storage under limiting conditions during the growing period. We believe that wood formation is highly dependent on the balance between the previous accumulation of carbohydrates and their consumption to maintain both respiration during dormancy and early spring growth.
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10
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Méndez-Cea B, García-García I, Sánchez-Salguero R, Lechuga V, Gallego FJ, Linares JC. Tree-Level Growth Patterns and Genetic Associations Depict Drought Legacies in the Relict Forests of Abies marocana. Plants (Basel) 2023; 12:873. [PMID: 36840220 PMCID: PMC9959318 DOI: 10.3390/plants12040873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/12/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
The frequency and intensity of drought events are increasing worldwide, challenging the adaptive capacity of several tree species. Here, we evaluate tree growth patterns and climate sensitivity to precipitation, temperature, and drought in the relict Moroccan fir Abies marocana. We selected two study sites, formerly stated as harboring contrasting A. marocana taxa (A. marocana and A. tazaotana, respectively). For each tree, dendrochronological methods were applied to quantify growth patterns and climate-growth sensitivity. Further, ddRAD-seq was performed on the same trees and close saplings to obtain single nucleotide polymorphisms (SNPs) and related genotype-phenotype associations. Genetic differentiation between the two studied remnant populations of A. marocana was weak. Growth patterns and climate-growth relationships were almost similar at the two sites studied, supporting a negative effect of warming. Growth trends and tree size showed associations with SNPs, although there were no relationships with phenotypes related to climatic sensitivity. We found significant differences in the SNPs subjected to selection in the saplings compared to the old trees, suggesting that relict tree populations might be subjected to genetic differentiation and local adaptation to climate dryness. Our results illustrate the potential of tree rings and genome-wide analysis to improve our understanding of the adaptive capacity of drought-sensitive forests to cope with ongoing climate change.
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Affiliation(s)
- Belén Méndez-Cea
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Isabel García-García
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Raúl Sánchez-Salguero
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - Víctor Lechuga
- Centro de Estudios Avanzados en Ciencias de la Tierra, Energía y Medio Ambiente (CEACTEMA), Universidad de Jaén, 23071 Jaén, Spain
| | - Francisco Javier Gallego
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Juan C. Linares
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
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11
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Liancourt P, Doležal J. Overgrowth competition or facilitation from cushion plants: Implication for the role of plant-plant interactions. Ecology 2023; 104:e3989. [PMID: 36756970 DOI: 10.1002/ecy.3989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/22/2022] [Accepted: 12/28/2022] [Indexed: 02/10/2023]
Affiliation(s)
- Pierre Liancourt
- Botany Department, State Museum of Natural History Stuttgart, Stuttgart, Germany.,Plant Ecology Group, University of Tübingen, Tübingen, Germany
| | - Jiri Doležal
- Institute of Botany, Czech Academy of Sciences, Pruhonice, Czech Republic.,Department of Botany, Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
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12
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Weigel R, Bat-Enerel B, Dulamsuren C, Muffler L, Weithmann G, Leuschner C. Summer drought exposure, stand structure, and soil properties jointly control the growth of European beech along a steep precipitation gradient in northern Germany. Glob Chang Biol 2023; 29:763-779. [PMID: 36426513 DOI: 10.1111/gcb.16506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 10/13/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
Increasing exposure to climate warming-related drought and heat threatens forest vitality in many regions on earth, with the trees' vulnerability likely depending on local climatic aridity, recent climate trends, edaphic conditions, and the drought acclimatization and adaptation of populations. Studies exploring tree species' vulnerability to climate change often have a local focus or model the species' entire distribution range, which hampers the separation of climatic and edaphic drivers of drought and heat vulnerability. We compared recent radial growth trends and the sensitivity of growth to drought and heat in central populations of a widespread and naturally dominant tree species in Europe, European beech (Fagus sylvatica), at 30 forest sites across a steep precipitation gradient (500-850 mm year-1 ) of short length to assess the species' adaptive potential. Size-standardized basal area increment remained more constant during the period of accelerated warming since the early 1980s in populations with >360 mm growing season precipitation (April-September), while growth trends were negative at sites with <360 mm. Climatic drought in June appeared as the most influential climatic factor affecting radial growth, with a stronger effect at drier sites. A decadal decrease in the climatic water balance of the summer was identified as the most important factor leading to growth decline, which is amplified by higher stem densities. Inter-annual growth variability has increased since the early 1980s, and variability is generally higher at drier and sandier sites. Similarly, within-population growth synchrony is higher at sandier sites and has increased with a decrease in the June climatic water balance. Our results caution against predicting the drought vulnerability of trees solely from climate projections, as soil properties emerged as an important modulating factor. We conclude that beech is facing recent growth decline at drier sites in the centre of its distribution range, driven by climate change-related climate aridification.
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Affiliation(s)
- Robert Weigel
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
| | - Banzragch Bat-Enerel
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
| | | | - Lena Muffler
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
| | - Greta Weithmann
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
| | - Christoph Leuschner
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
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13
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Copes‐Gerbitz K, Daniels LD, Hagerman SM. The contribution of Indigenous stewardship to an historical mixed-severity fire regime in British Columbia, Canada. Ecol Appl 2023; 33:e2736. [PMID: 36104834 PMCID: PMC10078449 DOI: 10.1002/eap.2736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 06/15/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
Indigenous land stewardship and mixed-severity fire regimes both promote landscape heterogeneity, and the relationship between them is an emerging area of research. In our study, we reconstructed the historical fire regime of Ne Sextsine, a 5900-ha dry, Douglas fir-dominated forest in the traditional territory of the T'exelc (Williams Lake First Nation) in British Columbia, Canada. Between 1550 and 1982 CE, we found median fire intervals of 18 years at the plot level and 4 years at the study-site level. Ne Sextsine was characterized by an historical mixed-severity fire regime, dominated by frequent, low-severity fires as indicated by fire scars, with infrequent, mixed-severity fires indicated by cohorts. Differentiating low- from mixed-severity plots over time was key to understanding the drivers of the fire regime at Ne Sextsine. Low-severity plots were coincident with areas of highest use by the T'exelc, including winter village sites, summer fishing camps, and travel corridors. The high fire frequency in low-severity plots ceased in the 1870s, following the smallpox epidemic, the forced relocation of Indigenous peoples into small reserves, and the prohibition of Indigenous burning. In contrast, the mixed-severity plots were coincident with areas where forest resources, such as deer or certain berry species, were important. The high fire frequency in the mixed-severity plots continued until the 1920s when industrial-scale grazing and logging began, facilitated by the establishment of a nearby railway. T'exelc oral histories and archeological evidence at Ne Sextsine speak to varied land stewardship, reflected in the spatiotemporal complexity of low- and mixed-severity fire plots. Across Ne Sextsine, 63% of cohorts established and persisted in the absence of fire after colonial impacts beginning in the 1860s, resulting in a dense, homogeneous landscape that no longer supports T'exelc values and is more likely to burn at uncharacteristic high severities. This nuanced understanding of the Indigenous contribution to a mixed-severity fire regime is critical for advancing proactive fire mitigation that is ecoculturally relevant and guided by Indigenous expertise.
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Affiliation(s)
- Kelsey Copes‐Gerbitz
- Department of Forest and Conservation Sciences, Faculty of ForestryUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Lori D. Daniels
- Department of Forest and Conservation Sciences, Faculty of ForestryUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Shannon M. Hagerman
- Department of Forest Resources Management, Faculty of ForestryUniversity of British ColumbiaVancouverBritish ColumbiaCanada
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14
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Tumajer J, Begović K, Čada V, Jenicek M, Lange J, Mašek J, Kaczka RJ, Rydval M, Svoboda M, Vlček L, Treml V. Ecological and methodological drivers of non-stationarity in tree growth response to climate. Glob Chang Biol 2023; 29:462-476. [PMID: 36200330 DOI: 10.1111/gcb.16470] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
Radial tree growth is sensitive to environmental conditions, making observed growth increments an important indicator of climate change effects on forest growth. However, unprecedented climate variability could lead to non-stationarity, that is, a decoupling of tree growth responses from climate over time, potentially inducing biases in climate reconstructions and forest growth projections. Little is known about whether and to what extent environmental conditions, species, and model type and resolution affect the occurrence and magnitude of non-stationarity. To systematically assess potential drivers of non-stationarity, we compiled tree-ring width chronologies of two conifer species, Picea abies and Pinus sylvestris, distributed across cold, dry, and mixed climates. We analyzed 147 sites across the Europe including the distribution margins of these species as well as moderate sites. We calibrated four numerical models (linear vs. non-linear, daily vs. monthly resolution) to simulate growth chronologies based on temperature and soil moisture data. Climate-growth models were tested in independent verification periods to quantify their non-stationarity, which was assessed based on bootstrapped transfer function stability tests. The degree of non-stationarity varied between species, site climatic conditions, and models. Chronologies of P. sylvestris showed stronger non-stationarity compared with Picea abies stands with a high degree of stationarity. Sites with mixed climatic signals were most affected by non-stationarity compared with sites sampled at cold and dry species distribution margins. Moreover, linear models with daily resolution exhibited greater non-stationarity compared with monthly-resolved non-linear models. We conclude that non-stationarity in climate-growth responses is a multifactorial phenomenon driven by the interaction of site climatic conditions, tree species, and methodological features of the modeling approach. Given the existence of multiple drivers and the frequent occurrence of non-stationarity, we recommend that temporal non-stationarity rather than stationarity should be considered as the baseline model of climate-growth response for temperate forests.
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Affiliation(s)
- Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Krešimir Begović
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Vojtěch Čada
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Michal Jenicek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jelena Lange
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiří Mašek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Ryszard J Kaczka
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Miloš Rydval
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Miroslav Svoboda
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Lukáš Vlček
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Hydrodynamics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
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15
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Fulé PZ, Sánchez Meador AJ, Moore MM, Covington WW, Kolb TE, Huffman DW, Normandin DP, Roccaforte JP. Forest restoration treatments increased growth and did not change survival of ponderosa pines in severe drought, Arizona. Ecol Appl 2022; 32:e2717. [PMID: 36184740 DOI: 10.1002/eap.2717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 05/15/2022] [Accepted: 06/13/2022] [Indexed: 06/16/2023]
Abstract
We report on survival and growth of ponderosa pines (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) 2 decades after forest restoration treatments in the G. A. Pearson Natural Area, northern Arizona. Despite protection from harvest that conserved old trees, a dense forest susceptible to uncharacteristically severe disturbance had developed during more than a century of exclusion of the previous frequent surface-fire regime that ceased upon Euro-American settlement in approximately 1876. Trees were thinned in 1993 to emulate prefire-exclusion forest conditions, accumulated forest floor was removed, and surface fire was re-introduced at 4-years intervals (full restoration). There was also a partial restoration treatment consisting of thinning alone. Compared with untreated controls, mortality of old trees (mean age 243 years, maximum 462 years) differed by <1 tree ha-1 and old-tree survival was statistically indistinguishable between treatments (90.5% control, 92.3% full, 82.6% partial). Post-treatment growth as measured by basal area increment of both old (pre-1876) and young (post-1876) pines was significantly higher in both treatments than counterpart control trees for more than 2 decades following thinning. Drought meeting the definition of megadrought affected the region almost all the time since the onset of the experiment, including 3 years that were severely dry. Growth of all trees declined in the driest 3 years, but old and young treated trees had significantly less decline. Association of tree growth with temperature (negative correlation) and precipitation (positive correlation) was much weaker in treated trees, indicating that they may experience less growth decline from warmer, drier conditions predicted in future decades. Overall, tree responses after the first 2 decades following treatment suggest that forest restoration treatments have led to substantial, sustained improvement in the growth of old and young ponderosa pines without affecting old-tree survival, thereby improving resilience to a warming climate.
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Affiliation(s)
- Peter Z Fulé
- School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA
| | - Andrew J Sánchez Meador
- School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA
- Ecological Restoration Institute, Northern Arizona University, Flagstaff, Arizona, USA
| | - Margaret M Moore
- School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA
| | - W Wallace Covington
- School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA
- Ecological Restoration Institute, Northern Arizona University, Flagstaff, Arizona, USA
| | - Thomas E Kolb
- School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA
| | - David W Huffman
- Ecological Restoration Institute, Northern Arizona University, Flagstaff, Arizona, USA
| | - Donald P Normandin
- Ecological Restoration Institute, Northern Arizona University, Flagstaff, Arizona, USA
| | - John Paul Roccaforte
- Ecological Restoration Institute, Northern Arizona University, Flagstaff, Arizona, USA
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16
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Roibu CC, Palaghianu C, Nagavciuc V, Ionita M, Sfecla V, Mursa A, Crivellaro A, Stirbu MI, Cotos MG, Popa A, Sfecla I, Popa I. The Response of Beech ( Fagus sylvatica L.) Populations to Climate in the Easternmost Sites of Its European Distribution. Plants (Basel) 2022; 11:3310. [PMID: 36501348 PMCID: PMC9738208 DOI: 10.3390/plants11233310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
In the context of forecasted climate change scenarios, the growth of forest tree species at their distribution margin is crucial to adapt current forest management strategies. Analyses of beech (Fagus sylvatica L.) growth have shown high plasticity, but easternmost beech populations have been rarely studied. To describe the response of the marginal beech population to the climate in the far east sites of its distribution, we first compiled new tree ring width chronologies. Then we analyzed climate-growth relationships for three marginal beech populations in the Republic of Moldova. We observed a relatively high growth rate in the marginal populations compared to core distribution sites. Our analyses further revealed a distinct and significant response of beech growth to all climatic variables, assessing for the first time the relationship between growth and vapor pressure deficit (VPD) which described how plant growth responds to drought. These results highlight that accumulated water deficit is an essential limiting factor of beech growth in this region. In conclusion, beech growth in the easternmost marginal population is drought-limited, and the sensitivity to VPD will need to be considered in future studies to update the forest management of other economic and ecologically important species.
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Affiliation(s)
- Cătălin-Constantin Roibu
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Ciprian Palaghianu
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Viorica Nagavciuc
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
- Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen Street No. 12, 27570 Bremerhaven, Germany
| | - Monica Ionita
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
- Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen Street No. 12, 27570 Bremerhaven, Germany
| | - Victor Sfecla
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
- Forestry and Plants Protection Department, Technical University of Moldova, Block 1, Stefan cel Mare si Sfant Boulevard 168, MD-2004 Chișinău, Moldova
| | - Andrei Mursa
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Alan Crivellaro
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Marian-Ionut Stirbu
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Mihai-Gabriel Cotos
- Forest Biometrics Laboratory, Faculty of Forestry, “Ștefan cel Mare” University of Suceava, Universității Street, No. 13, 720229 Suceava, Romania
| | - Andrei Popa
- National Research and Development Institute for Silviculture “Marin Drăcea”, Calea Bucovinei No. 76bis, 725100 Câmpulung Moldovenesc, Romania
- Faculty of Silviculture and Forest Engineering, Transilvania University of Brașov, 500036 Brașov, Romania
| | - Irina Sfecla
- Forestry and Plants Protection Department, Technical University of Moldova, Block 1, Stefan cel Mare si Sfant Boulevard 168, MD-2004 Chișinău, Moldova
- “Alexandru Ciubotaru” National Botanical Garden (Institute), 18 Padurii, str., MD-2002 Chisinau, Moldova
| | - Ionel Popa
- National Research and Development Institute for Silviculture “Marin Drăcea”, Calea Bucovinei No. 76bis, 725100 Câmpulung Moldovenesc, Romania
- Center of Mountain Economy, INCE-CE-MONT Vatra Dornei, Petreni Street No. 49, 725700 Vatra Dornei, Romania
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17
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Laffitte B, Seyler BC, Wang W, Li P, Du J, Tang Y. Declining tree growth rates despite increasing water-use efficiency under elevated CO 2 reveals a possible global overestimation of CO 2 fertilization effect. Heliyon 2022; 8:e11219. [PMID: 36339991 PMCID: PMC9626951 DOI: 10.1016/j.heliyon.2022.e11219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/27/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
Though rising atmospheric CO2 concentrations (Ca) harm the environment and society, they may also raise photosynthetic rates and enhance intrinsic water-use efficiency (iWUE). Numerous short-term studies have investigated tree growth under elevated CO2 (eCO2) conditions, but no long-duration study has investigated eCO2 impacts on tree growth and iWUE under natural conditions. Utilizing a new dendrochronological experimental design in a heavily-touristed nature preserve in Southwest China (Jiuzhaigou National Nature Reserve), we compared tree growth (e.g., basal area increment) and iWUE in two biophysically and environmentally similar valleys with contrasting anthropogenic activities. Trees in the control valley with ambient CO2 benefited from increasing Ca, possibly due to the CO2 fertilization effect and optimal environmental conditions. However, trees in the treatment valley with intensive tourism experienced comparatively higher localized eCO2 and growth rate declines. While iWUE increased (1959–2017) in the control (25.3%) and treatment sites (47.8%), declining tree growth rates in the treatment site was likely because comparatively extreme CO2 exposure levels encouraged stomatal closures. As the first long-term study investigating eCO2 impacts on tree growth and iWUE under natural conditions, we demonstrate that increased forest iWUE is unlikely to overcome negative drought stress and rising temperature impacts. Thus, forest potential for mitigating eCO2 and global climate change is likely overestimated, particularly under dry temperate conditions.
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Affiliation(s)
- Benjamin Laffitte
- Department of Environment, College of Architecture and Environment, Sichuan University, No. 24, South Section One, First Ring Road, Chengdu, Sichuan 610065, China
| | - Barnabas C. Seyler
- Department of Environment, College of Architecture and Environment, Sichuan University, No. 24, South Section One, First Ring Road, Chengdu, Sichuan 610065, China
| | - Wenzhi Wang
- The Key Laboratory of Mountain Environment Evolution and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China
| | - Pengbo Li
- Department of Environment, College of Architecture and Environment, Sichuan University, No. 24, South Section One, First Ring Road, Chengdu, Sichuan 610065, China
| | - Jie Du
- Jiuzhaigou Administrative Bureau, Zhangzha, Jiuzhaigou, Sichuan 623402, China
| | - Ya Tang
- Department of Environment, College of Architecture and Environment, Sichuan University, No. 24, South Section One, First Ring Road, Chengdu, Sichuan 610065, China,Corresponding author.
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Girardin MP, Guo XJ, Gervais D, Metsaranta J, Campbell EM, Arsenault A, Isaac-Renton M, Hogg EH. Cold-season freeze frequency is a pervasive driver of subcontinental forest growth. Proc Natl Acad Sci U S A 2022; 119:e2117464119. [PMID: 35476522 DOI: 10.1073/pnas.2117464119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
SignificanceThe reduction of freeze exposure with winter warming has consequences for carbon sequestration by northern forests. Quantifying the impact of these changes on tree growth is, however, challenging because of among- and within-tree species variability in freeze tolerance and phenological cues. Here, we provide a comprehensive assessment of tree growth response to the cold-season frequency of freeze days using an extensive tree-ring dataset covering Canada's forests. Our study shows that tree growth responses to freeze exposure vary in direction and magnitude by clade and species but also with leaf-out strategy, tree age and size, and environmental factors. Such quantification can help predict terrestrial carbon dynamics under climate change.
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Jia G, Chen L, Yu X, Liu Z. Soil water stress overrides the benefit of water-use efficiency from rising CO 2 and temperature in a cold semi-arid poplar plantation. Plant Cell Environ 2022; 45:1172-1186. [PMID: 35037279 DOI: 10.1111/pce.14260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 09/15/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
The counteractive effect of atmospheric CO2 (ca ) enrichment and drought stress on tree growth results in great uncertainty in the growth patterns of forest plantations in cold semi-arid regions. We analysed tree ring chronologies and carbon isotopes in Populus simonii plantations in cold semi-arid areas in northern China over the past four decades. We hypothesized that the hydraulic stress from drought would override the stimulating effect of increasing ca and temperature (T) on stem growth (basal area increment [BAI]). We found the stimulating effect of rising ca and T on the growth, indicated by continuous increase of intrinsic water-use efficiency in all stands and a positive correlation between T and BAI. However, these effects failed to alleviate the negative impacts of drought on tree growth. Concurrent acceleration of BAI reversed during the intensive drought episodes. Water stress resulted from inaccessibility of roots to deep soil water rather than from lack of precipitation, suggested by the decoupling of BAI from precipitation and vapour pressure deficit. Local soil water limitation might also cause greater stomatal regulation in declining trees, indicated by lower intercellular CO2 concentration. Thus, site-specific soil moisture conditions growth sensitivity to global warming resulting in site-specific decline episodes in drought-prone areas.
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Affiliation(s)
- Guodong Jia
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry University, Beijing, China
- School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Lixin Chen
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry University, Beijing, China
- School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Xinxiao Yu
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry University, Beijing, China
- School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
| | - Ziqiang Liu
- School of Forestry, Nanjing Forestry University, Nanjing, China
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20
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Boakye EA, Houle D, Bergeron Y, Girardin MP, Drobyshev I. Insect defoliation modulates influence of climate on the growth of tree species in the boreal mixed forests of eastern Canada. Ecol Evol 2022; 12:e8656. [PMID: 35342593 PMCID: PMC8932224 DOI: 10.1002/ece3.8656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 01/25/2022] [Accepted: 02/06/2022] [Indexed: 11/06/2022] Open
Abstract
Increasing air temperatures and changing precipitation patterns due to climate change can affect tree growth in boreal forests. Periodic insect outbreaks affect the growth trajectory of trees, making it difficult to quantify the climate signal in growth dynamics at scales longer than a year. We studied climate-driven growth trends and the influence of spruce budworm (Choristoneura fumiferana Clem.) outbreaks on these trends by analyzing the basal area increment (BAI) of 2058 trees of Abies balsamea (L.) Mill., Picea glauca (Moench) Voss, Thuja occidentalis L., Populus tremuloides Michx., and Betula papyrifera Marsh, which co-occurs in the boreal mixedwood forests of western Quebec. We used a generalized additive mixed model (GAMM) to analyze species-specific trends in BAI dynamics from 1967 to 1991. The model relied on tree size, cambial age, degree of spruce budworm defoliation, and seasonal climatic variables. Overall, we observed a decreasing growth rate of the spruce budworm host species, A. balsamea and P. glauca between 1967 and 1991, and an increasing growth rate for the non-host, P. tremuloides, B. papyrifera, and T. occidentalis. Our results suggest that insect outbreaks may offset growth increases resulting from a warmer climate. The observation warrants the inclusion of the spruce budworm defoliation into models predicting future forest productivity.
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Affiliation(s)
- Emmanuel Amoah Boakye
- Chaire industrielle CRSNG‐UQAT‐UQAM en aménagement forestier durableInstitut de Recherche Sur Les ForêtsUniversité du Québec en Abitibi‐Témiscamingue (UQAT)Rouyn‐NorandaQuébecCanada
| | - Daniel Houle
- Ministère des Forêts, de la Faune et des ParcsDirection de la recherché forestièreQuébecQuébecCanada
- Ouranos Climate Change ConsortiumMontréalQuébecCanada
| | - Yves Bergeron
- Chaire industrielle CRSNG‐UQAT‐UQAM en aménagement forestier durableInstitut de Recherche Sur Les ForêtsUniversité du Québec en Abitibi‐Témiscamingue (UQAT)Rouyn‐NorandaQuébecCanada
- Forest Research CentreUniversité du Québec à MontréalMontréalQuébecCanada
| | - Martin P. Girardin
- Natural Resources CanadaCanadian Forest ServiceLaurentian Forestry CentreQuébecQuébecCanada
| | - Igor Drobyshev
- Chaire industrielle CRSNG‐UQAT‐UQAM en aménagement forestier durableInstitut de Recherche Sur Les ForêtsUniversité du Québec en Abitibi‐Témiscamingue (UQAT)Rouyn‐NorandaQuébecCanada
- Southern Swedish Forest Research CentreSwedish University of Agricultural SciencesAlnarpSweden
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21
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Dulamsuren C, Hauck M. Drought stress mitigation by nitrogen in boreal forests inferred from stable isotopes. Glob Chang Biol 2021; 27:5211-5224. [PMID: 34309985 DOI: 10.1111/gcb.15813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/21/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
Forest growth in most parts of the boreal zone is originally limited by low temperatures and low nitrogen availability. Due to the rapid climate warming at high latitudes, an increasing forest area is switching to drought limitation, especially in continental and southern parts of the boreal forest. Studies addressing this issue were mostly dendrochronological and remote-sensing analyses focusing on climatic effects, but not answering the question whether drought is effective alone or in combination with nitrogen shortage at limiting the forests' productivity and vitality. Here we show in a case study from larch forests of Mongolia with a combination of stable isotope analyses, tree-ring analysis and bioindication of the local variability of livestock densities using epiphytic lichens that, in the studied highly drought-prone forests at the southern fringe of the boreal forest in Inner Asia, the trees' vulnerability to drought is modified by nitrogen fertilization from livestock kept in the vicinity and the edge of the forests. The most likely mechanism behind this drought-nitrogen interaction is the reduction of stomatal conductance, which is known to be induced by low nitrogen levels in plants. Nitrogen fertilization by the livestock could, thus, shorten the times of stomatal closure and thereby increase tree growth, which we measured as radial stem increment. Even though the underlying mechanisms, which were so far examined in angiosperms, should be experimentally tested for conifers, our results indicate that focusing on water alone is not enough to understand the climate change response of drought-limited boreal forests.
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Affiliation(s)
| | - Markus Hauck
- Applied Vegetation Ecology, University of Freiburg, Freiburg, Germany
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22
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Abstract
Large, majestic trees are iconic symbols of great age among living organisms. Published evidence suggests that trees do not die because of genetically programmed senescence in their meristems, but rather are killed by an external agent or a disturbance event. Long tree lifespans are therefore allowed by specific combinations of life history traits within realized niches that support resistance to, or avoidance of, extrinsic mortality. Another requirement for trees to achieve their maximum longevity is either sustained growth over extended periods of time or at least the capacity to increase their growth rates when conditions allow it. The growth plasticity and modularity of trees can then be viewed as an evolutionary advantage that allows them to survive and reproduce for centuries and millennia. As more and more scientific information is systematically collected on tree ages under various ecological settings, it is becoming clear that tree longevity is a key trait for global syntheses of life history strategies, especially in connection with disturbance regimes and their possible future modifications. In addition, we challenge the long-held notion that shade-tolerant, late-successional species have longer lifespans than early-successional species by pointing out that tree species with extreme longevity do not fit this paradigm. Identifying extremely old trees is therefore the groundwork not only for protecting and/or restoring entire landscapes, but also to revisit and update classic ecological theories that shape our understanding of environmental change.
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Affiliation(s)
- Gianluca Piovesan
- Dendrology Lab, Department of Agriculture and Forest Sciences (DAFNE), University of Tuscia, Viterbo, 01100, Italy
| | - Franco Biondi
- DendroLab, Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV, 89557, USA
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Arnič D, Gričar J, Jevšenak J, Božič G, von Arx G, Prislan P. Different Wood Anatomical and Growth Responses in European Beech ( Fagus sylvatica L.) at Three Forest Sites in Slovenia. Front Plant Sci 2021; 12:669229. [PMID: 34381473 PMCID: PMC8349990 DOI: 10.3389/fpls.2021.669229] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 07/05/2021] [Indexed: 06/13/2023]
Abstract
European beech (Fagus sylvatica L.) adapts to local growing conditions to enhance its performance. In response to variations in climatic conditions, beech trees adjust leaf phenology, cambial phenology, and wood formation patterns, which result in different tree-ring widths (TRWs) and wood anatomy. Chronologies of tree ring width and vessel features [i.e., mean vessel area (MVA), vessel density (VD), and relative conductive area (RCTA)] were produced for the 1960-2016 period for three sites that differ in climatic regimes and spring leaf phenology (two early- and one late-flushing populations). These data were used to investigate long-term relationships between climatic conditions and anatomical features of four quarters of tree-rings at annual and intra-annual scales. In addition, we investigated how TRW and vessel features adjust in response to extreme weather events (i.e., summer drought). We found significant differences in TRW, VD, and RCTA among the selected sites. Precipitation and maximum temperature before and during the growing season were the most important climatic factors affecting TRW and vessel characteristics. We confirmed differences in climate-growth relationships between the selected sites, late flushing beech population at Idrija showing the least pronounced response to climate. MVA was the only vessel trait that showed no relationship with TRW or other vessel features. The relationship between MVA and climatic factors evaluated at intra-annual scale indicated that vessel area in the first quarter of tree-ring were mainly influenced by climatic conditions in the previous growing season, while vessel area in the second to fourth quarters of tree ring width was mainly influenced by maximum temperature and precipitation in the current growing season. When comparing wet and dry years, beech from all sites showed a similar response, with reduced TRW and changes in intra-annual variation in vessel area. Our findings suggest that changes in temperature and precipitation regimes as predicted by most climate change scenarios will affect tree-ring increments and wood structure in beech, yet the response between sites or populations may differ.
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Affiliation(s)
- Domen Arnič
- Department for Forest Technique and Economics, Slovenian Forestry Institute, Ljubljana, Slovenia
- Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Jožica Gričar
- Department of Forest Yield and Silviculture, Slovenian Forestry Institute, Ljubljana, Slovenia
| | - Jernej Jevšenak
- Department of Forest Yield and Silviculture, Slovenian Forestry Institute, Ljubljana, Slovenia
| | - Gregor Božič
- Department of Forest Physiology and Genetics, Slovenian Forestry Institute, Ljubljana, Slovenia
| | - Georg von Arx
- Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Peter Prislan
- Department for Forest Technique and Economics, Slovenian Forestry Institute, Ljubljana, Slovenia
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24
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Barbosa ACF, Gerolamo CS, Lima AC, Angyalossy V, Pace MR. Polishing entire stems and roots using sandpaper under water: An alternative method for macroscopic analyses. Appl Plant Sci 2021; 9:APS311421. [PMID: 34141498 PMCID: PMC8202830 DOI: 10.1002/aps3.11421] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/22/2021] [Indexed: 05/11/2023]
Abstract
PREMISE Polishing entire stem and root samples is an effective method for studying their anatomy; however, polishing fresh samples to preserve woods with soft tissues or barks is challenging given that soft tissues shrink when dried. We propose sanding fresh or liquid-preserved samples under water as an alternative, given that it preserves all tissues in an intact and clear state. METHODS AND RESULTS By manually grinding the surface of the samples under water using three ascending grits of waterproof sandpapers, an excellent polished sanded surface is obtained. The wood swarf goes into the water without clogging the cell lumina, rendering the surfaces adequate for cell visualization and description. We show results in palms, liana stems, roots, and wood blocks. CONCLUSIONS Using this simple, inexpensive, rapid technique, it is possible to polish either fresh, dry, or liquid-preserved woody plant samples, preserving the integrity of both the soft and hard tissues and allowing for detailed observations of the stems and roots.
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Affiliation(s)
- Antonio C. F. Barbosa
- Laboratório de Madeira e Produtos DerivadosCentro de Tecnologia de Recursos FlorestaisInstituto de Pesquisas TecnológicasAv. Prof. Almeida Prado 532, Cidade UniversitáriaSão Paulo05508‐901Brazil
| | - Caian S. Gerolamo
- Laboratório de Anatomia VegetalInstituto de BiociênciasDepartamento de BotânicaUniversidade de São PauloRua do Matão 277, Cidade UniversitáriaSão Paulo05508‐090Brazil
| | - André C. Lima
- Weizmann Tree LabDepartment of Plant and Environmental SciencesWeizmann Institute of ScienceHerzl Street 234Rehovot76100Israel
| | - Veronica Angyalossy
- Laboratório de Anatomia VegetalInstituto de BiociênciasDepartamento de BotânicaUniversidade de São PauloRua do Matão 277, Cidade UniversitáriaSão Paulo05508‐090Brazil
| | - Marcelo R. Pace
- Departamento de BotánicaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoCircuito Zona Deportiva s/n de Ciudad UniversitariaMexico City04510Mexico
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Chavarie L, Voelker S, Hansen MJ, Bronte CR, Muir AM, Zimmerman MS, Krueger CC. Temporal instability of lake charr phenotypes: Synchronicity of growth rates and morphology linked to environmental variables? Evol Appl 2021; 14:1159-1177. [PMID: 33897827 PMCID: PMC8061271 DOI: 10.1111/eva.13188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 12/24/2022] Open
Abstract
Pathways through which phenotypic variation among individuals arise can be complex. One assumption often made in relation to intraspecific diversity is that the stability or predictability of the environment will interact with expression of the underlying phenotypic variation. To address biological complexity below the species level, we investigated variability across years in morphology and annual growth increments between and within two sympatric lake charr Salvelinus namaycush ecotypes in Rush Lake, USA. A rapid phenotypic shift in body and head shape was found within a decade. The magnitude and direction of the observed phenotypic change were consistent in both ecotypes, which suggests similar pathways caused the variation over time. Over the same time period, annual growth increments declined for both lake charr ecotypes and corresponded with a consistent phenotypic shift of each ecotype. Despite ecotype-specific annual growth changes in response to winter conditions, the observed annual growth shift for both ecotypes was linked, to some degree, with variation in the environment. Particularly, a declining trend in regional cloud cover was associated with an increase of early-stage (ages 1-3) annual growth for lake charr of Rush Lake. Underlying mechanisms causing changes in growth rates and constrained morphological modulation are not fully understood. An improved knowledge of the biology hidden within the expression of phenotypic variation promises to clarify our understanding of temporal morphological diversity and instability.
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Affiliation(s)
- Louise Chavarie
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life SciencesÅsNorway
- Beaty Biodiversity Research CenterUniversity of British ColumbiaVancouverBCCanada
- Scottish Centre for Ecology and the Natural EnvironmentIBAHCM, Rowardennan, Loch LomondGlasgowUK
| | - Steve Voelker
- SUNY College of Environmental Science and ForestrySyracuseNYUSA
| | | | - Charles R. Bronte
- U.S. Fish and Wildlife ServiceGreen Bay Fish and Wildlife Conservation OfficeNew FrankenWIUSA
| | | | | | - Charles C. Krueger
- Department of Fisheries and WildlifeCenter for Systems Integration and SustainabilityMichigan State UniversityEast LansingMIUSA
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Demidko DA, Trefilova OV, Kulakov SS, Mikhaylov PV. Pine Looper Bupalus piniaria (L.) Outbreaks Reconstruction: A Case Study for Southern Siberia. Insects 2021; 12:90. [PMID: 33494208 DOI: 10.3390/insects12020090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/15/2021] [Accepted: 01/19/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary The pine looper damages Scots pine forests over vast areas. However, the study of its population fluctuations is hampered by the lack of long-term observation series. The dendrochronological reconstruction is often used to study the history of its outbreaks. In some cases, such reconstructions require methods that work without comparison with other tree species. We have proposed such a technique based on the analysis of the early- and latewood growth. The technique makes it possible to separate the effect of defoliation on tree rings from weather influence. Besides, it is more sensitive than previously developed methods when reconstructing outbreaks of the pine looper. The history of outbreaks reconstructed by the technique for the West Siberian Plain’s forest-steppe includes 11 defoliation events from 1914 to 2017. The results obtained using the developed method are useful to better understand the patterns of population dynamics of the pine looper and other phyllophagous pests. Abstract The pine looper Bupalus piniaria is one of the most widespread phyllophagous insect species across Northern Eurasia, defoliating Scots pine forests over vast territories. Since there are not enough long-term documented observations on a series of outbreaks, there is a need for methods allowing them to be reconstructed to study their dynamics patterns. Previously, dendrochronological methods were successfully used to solve such issues. However, the most common approach is not applicable for the Western Siberian forest-steppe since it requires comparison with a non-damaged tree species close to pine in terms of longevity and resistance to rot. In the pine forests of the steppe and forest-steppe zones of Western Siberia, there are no species that are not damaged by the pine looper that meets these requirements. Methods allowing not using control species are also not free from disadvantages (e.g., weak specificity). Therefore, we have developed a new method based on the analysis, not of the tree-ring width but the early- and latewood width to reconstruct past defoliation events. The past defoliation by the pine looper is indicated by the presence of a negative pointer year for latewood, followed by a negative pointer year for earlywood in a subsequent year among the majority of individuals. Linear modeling showed a difference between the climate impact on radial growth and the defoliation one. The obtained reconstruction was compared with the results of other methods (mowing window, OUTBREAK, independent component analysis), literature, and Forest Service data. The developed new method (pointer year method; PYM) showed high efficiency confirmed by results of the tree-ring series analysis (11 revealed outbreaks in the past). Compared with other reconstruction techniques under the given conditions (a favorable combination of heat and humidity; probably low-intense and short defoliation), the proposed method provided more precise results than those proposed earlier. Due to high accuracy, the PYM can be useful for detecting late-summer and autumn past defoliations of tree species with clear difference between early- and latewood even though the damage was weak.
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Tumajer J, Kašpar J, Kuželová H, Shishov VV, Tychkov II, Popkova MI, Vaganov EA, Treml V. Forward Modeling Reveals Multidecadal Trends in Cambial Kinetics and Phenology at Treeline. Front Plant Sci 2021; 12:613643. [PMID: 33584770 PMCID: PMC7875878 DOI: 10.3389/fpls.2021.613643] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/06/2021] [Indexed: 05/02/2023]
Abstract
Significant alterations of cambial activity might be expected due to climate warming, leading to growing season extension and higher growth rates especially in cold-limited forests. However, assessment of climate-change-driven trends in intra-annual wood formation suffers from the lack of direct observations with a timespan exceeding a few years. We used the Vaganov-Shashkin process-based model to: (i) simulate daily resolved numbers of cambial and differentiating cells; and (ii) develop chronologies of the onset and termination of specific phases of cambial phenology during 1961-2017. We also determined the dominant climatic factor limiting cambial activity for each day. To asses intra-annual model validity, we used 8 years of direct xylogenesis monitoring from the treeline region of the Krkonoše Mts. (Czechia). The model exhibits high validity in case of spring phenological phases and a seasonal dynamics of tracheid production, but its precision declines for estimates of autumn phenological phases and growing season duration. The simulations reveal an increasing trend in the number of tracheids produced by cambium each year by 0.42 cells/year. Spring phenological phases (onset of cambial cell growth and tracheid enlargement) show significant shifts toward earlier occurrence in the year (for 0.28-0.34 days/year). In addition, there is a significant increase in simulated growth rates during entire growing season associated with the intra-annual redistribution of the dominant climatic controls over cambial activity. Results suggest that higher growth rates at treeline are driven by (i) temperature-stimulated intensification of spring cambial kinetics, and (ii) decoupling of summer growth rates from the limiting effect of low summer temperature due to higher frequency of climatically optimal days. Our results highlight that the cambial kinetics stimulation by increasing spring and summer temperatures and shifting spring phenology determine the recent growth trends of treeline ecosystems. Redistribution of individual climatic factors controlling cambial activity during the growing season questions the temporal stability of climatic signal of cold forest chronologies under ongoing climate change.
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Affiliation(s)
- Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
- Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, Germany
- *Correspondence: Jan Tumajer,
| | - Jakub Kašpar
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
| | - Hana Kuželová
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
| | - Vladimir V. Shishov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
- Sukachev Institute of Forest SB RAS, Krasnoyarsk, Russia
| | - Ivan I. Tychkov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Margarita I. Popkova
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Eugene A. Vaganov
- Sukachev Institute of Forest SB RAS, Krasnoyarsk, Russia
- Rectorate, Siberian Federal University, Krasnoyarsk, Russia
- Center for Forest Ecology and Productivity of the Russian Academy of Sciences, Moscow, Russia
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
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Locosselli GM, Brienen RJW, Leite MS, Gloor M, Krottenthaler S, Oliveira AA, Barichivich J, Anhuf D, Ceccantini G, Schöngart J, Buckeridge M. Global tree-ring analysis reveals rapid decrease in tropical tree longevity with temperature. Proc Natl Acad Sci U S A 2020; 117:33358-64. [PMID: 33318167 DOI: 10.1073/pnas.2003873117] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Forests are the largest terrestrial biomass pool, with over half of this biomass stored in the highly productive tropical lowland forests. The future evolution of forest biomass depends critically on the response of tree longevity and growth rates to future climate. We present an analysis of the variation in tree longevity and growth rate using tree-ring data of 3,343 populations and 438 tree species and assess how climate controls growth and tree longevity across world biomes. Tropical trees grow, on average, two times faster compared to trees from temperate and boreal biomes and live significantly shorter, on average (186 ± 138 y compared to 322 ± 201 y outside the tropics). At the global scale, growth rates and longevity covary strongly with temperature. Within the warm tropical lowlands, where broadleaf species dominate the vegetation, we find consistent decreases in tree longevity with increasing aridity, as well as a pronounced reduction in longevity above mean annual temperatures of 25.4 °C. These independent effects of temperature and water availability on tree longevity in the tropics are consistent with theoretical predictions of increases in evaporative demands at the leaf level under a warmer and drier climate and could explain observed increases in tree mortality in tropical forests, including the Amazon, and shifts in forest composition in western Africa. Our results suggest that conditions supporting only lower tree longevity in the tropical lowlands are likely to expand under future drier and especially warmer climates.
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29
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Robinson E, Bocinsky RK, Bird D, Freeman J, Kelly RL. Dendrochronological dates confirm a Late Prehistoric population decline in the American Southwest derived from radiocarbon dates. Philos Trans R Soc Lond B Biol Sci 2020; 376:20190718. [PMID: 33250020 PMCID: PMC7741101 DOI: 10.1098/rstb.2019.0718] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The northern American Southwest provides one of the most well-documented cases of human population growth and decline in the world. The geographic extent of this decline in North America is unknown owing to the lack of high-resolution palaeodemographic data from regions across and beyond the greater Southwest, where archaeological radiocarbon data are often the only available proxy for investigating these palaeodemographic processes. Radiocarbon time series across and beyond the greater Southwest suggest widespread population collapses from AD 1300 to 1600. However, radiocarbon data have potential biases caused by variable radiocarbon sample preservation, sample collection and the nonlinearity of the radiocarbon calibration curve. In order to be confident in the wider trends seen in radiocarbon time series across and beyond the greater Southwest, here we focus on regions that have multiple palaeodemographic proxies and compare those proxies to radiocarbon time series. We develop a new method for time series analysis and comparison between dendrochronological data and radiocarbon data. Results confirm a multiple proxy decline in human populations across the Upland US Southwest, Central Mesa Verde and Northern Rio Grande from AD 1300 to 1600. These results lend confidence to single proxy radiocarbon-based reconstructions of palaeodemography outside the Southwest that suggest post-AD 1300 population declines in many parts of North America. This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’.
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Affiliation(s)
- Erick Robinson
- Department of Sociology, Social Work, and Anthropology, Utah State University, 0730 Old Main Hill, Logan, UT 84322-0730, USA
| | - R Kyle Bocinsky
- Crow Canyon Archaeological Center, 23390 Road K, Cortez, CO 81321, USA
| | - Darcy Bird
- Department of Anthropology, Washington State University, College Hall 150, PO Box 644910, Pullman, WA 99164-4910, USA
| | - Jacob Freeman
- Department of Sociology, Social Work, and Anthropology, Utah State University, 0730 Old Main Hill, Logan, UT 84322-0730, USA
| | - Robert L Kelly
- Department of Anthropology, University of Wyoming, 1000 E. University Ave, Laramie, WY 82070, USA
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McCarroll D, Duffy JE, Loader NJ, Young GHF, Davies D, Miles D, Bronk Ramsey C. Are there enormous age-trends in stable carbon isotope ratios of oak tree rings? Holocene 2020; 30:1637-1642. [PMID: 33071480 PMCID: PMC7543024 DOI: 10.1177/0959683620941073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
We test a recent prediction that stable carbon isotope ratios from UK oaks will display age-trends of more than 4‰ per century by measuring >5400 carbon isotope ratios from the late-wood alpha-cellulose of individual rings from 18 modern oak trees and 50 building timbers spanning the 9th-21st centuries. After a very short (c.5 years) juvenile phase with slightly elevated values, the number of series that show rising and falling trends is almost equal (33:35) and the average trend is almost zero. These results are based upon measuring and averaging the trends in individual time-series; the 'mean of the slopes' approach. We demonstrate that the more conventional 'slope of the mean' approach can produce strong but spurious 'age-trends' even when the constituent series are flat, with zero slope and zero variance. We conclude that it is safe to compile stable carbon isotope chronologies from UK oaks without de-trending. The isotope chronologies produced in this way are not subject to the 'segment length curse', which applies to growth measurements, such as ring width or density, and have the potential to retain very long-term climate signals.
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Affiliation(s)
- Danny McCarroll
- Department of Geography, Swansea University Singleton Park, Swansea, UK
| | - Josie E Duffy
- Department of Geography, Swansea University Singleton Park, Swansea, UK
| | - Neil J Loader
- Department of Geography, Swansea University Singleton Park, Swansea, UK
| | - Giles HF Young
- Department of Geography, Swansea University Singleton Park, Swansea, UK
- Natural Resources Institute Finland (Luke), Helsinki, Finland
| | - Darren Davies
- Department of Geography, Swansea University Singleton Park, Swansea, UK
| | - Daniel Miles
- Research Laboratory for Archaeology, Oxford University, South Parks Road, Oxford, UK
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Sabella E, Moretti S, Gärtner H, Luvisi A, De Bellis L, Vergine M, Saurer M, Cherubini P. Increase in ring width, vessel number and δ18O in olive trees infected with Xylella fastidiosa. Tree Physiol 2020; 40:1583-1594. [PMID: 32705131 DOI: 10.1093/treephys/tpaa095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Xylella fastidiosa (Xf) Wells, Raju et al., 1986 is a bacterium that causes plant diseases in the Americas. In Europe, it was first detected on the Salento Peninsula (Italy), where it was found to be associated with the olive quick decline syndrome. Here, we present the results of the first tree-ring study of infected and uninfected olive trees (Olea europaea L.) of two different cultivars, one resistant and one susceptible, to establish the effects induced by the spread of the pathogen inside the tree. Changes in wood anatomical characteristics, such as an increase in the number of vessels and in ring width, were observed in the infected plants of both the cultivars Cellina di Nardò (susceptible to Xf infection) and Leccino (resistant to Xf infection). Thus, whether infection affects the mortality of the tree or not, the tree shows a reaction to it. The presence of occlusions was detected in the wood of both 4-year-old branches and the tree stem core. As expected, the percentage of occluded vessels in the Xf-susceptible cultivar Cellina di Nardò was significantly higher than in the Xf-resistant cultivar Leccino. The δ 18O of the 4-year-old branches was significantly higher in infected trees of both cultivars than in noninfected trees, while no variations in δ 13C were observed. This suggests a reduction in leaf transpiration rates during infection and seems to be related to the occlusions observed in rings of the 4-year-old branches. Such occlusions can determine effects at leaf level that could influence stomatal activity. On the other hand, the significant increase in the number of vessels in infected trees could be related to the tree's attempt to enhance water conductivity in response to the pathogen-induced vessel occlusions.
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Affiliation(s)
- Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Samuele Moretti
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Laboratoire Vigne, Biotechnologies et Environnement (LVBE, EA 3991), Université de Haute-Alsace, 33 rue de Herrlisheim, 68008 Colmar Cedex, France
| | - Holger Gärtner
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Matthias Saurer
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Paolo Cherubini
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Forest and Conservation Sciences, University of British Columbia, 3041 - 2424 Main Mall, Vancouver, BC, Canada
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Zuidema PA, Heinrich I, Rahman M, Vlam M, Zwartsenberg SA, van der Sleen P. Recent CO 2 rise has modified the sensitivity of tropical tree growth to rainfall and temperature. Glob Chang Biol 2020; 26:4028-4041. [PMID: 32441438 PMCID: PMC7317543 DOI: 10.1111/gcb.15092] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 02/10/2020] [Accepted: 03/06/2020] [Indexed: 05/28/2023]
Abstract
Atmospheric CO2 (ca ) rise changes the physiology and possibly growth of tropical trees, but these effects are likely modified by climate. Such ca × climate interactions importantly drive CO2 fertilization effects of tropical forests predicted by global vegetation models, but have not been tested empirically. Here we use tree-ring analyses to quantify how ca rise has shifted the sensitivity of tree stem growth to annual fluctuations in rainfall and temperature. We hypothesized that ca rise reduces drought sensitivity and increases temperature sensitivity of growth, by reducing transpiration and increasing leaf temperature. These responses were expected for cooler sites. At warmer sites, ca rise may cause leaf temperatures to frequently exceed the optimum for photosynthesis, and thus induce increased drought sensitivity and stronger negative effects of temperature. We tested these hypotheses using measurements of 5,318 annual rings from 129 trees of the widely distributed (sub-)tropical tree species, Toona ciliata. We studied growth responses during 1950-2014, a period during which ca rose by 28%. Tree-ring data were obtained from two cooler (mean annual temperature: 20.5-20.7°C) and two warmer (23.5-24.8°C) sites. We tested ca × climate interactions, using mixed-effect models of ring-width measurements. Our statistical models revealed several significant and robust ca × climate interactions. At cooler sites (and seasons), ca × climate interactions showed good agreement with hypothesized growth responses of reduced drought sensitivity and increased temperature sensitivity. At warmer sites, drought sensitivity increased with increasing ca , as predicted, and hot years caused stronger growth reduction at high ca . Overall, ca rise has significantly modified sensitivity of Toona stem growth to climatic variation, but these changes depended on mean climate. Our study suggests that effects of ca rise on tropical tree growth may be more complex and less stimulatory than commonly assumed and require a better representation in global vegetation models.
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Affiliation(s)
- Pieter A. Zuidema
- Forest Ecology & Forest Management GroupWageningen UniversityWageningenThe Netherlands
| | - Ingo Heinrich
- Section Climate Dynamics and Landscape EvolutionGFZ German Research Centre for GeosciencesTelegrafenbergGermany
- Geography DepartmentHumboldt UniversityBerlinGermany
| | - Mizanur Rahman
- Institute of GeographyFriedrich‐Alexander University Erlangen‐NurembergErlangenGermany
- Department of Forestry and Environmental ScienceShahjalal University of Science and TechnologySylhetBangladesh
| | - Mart Vlam
- Forest Ecology & Forest Management GroupWageningen UniversityWageningenThe Netherlands
- Delta Areas and ResourcesVan Hall Larenstein University of Applied SciencesLeeuwardenThe Netherlands
| | | | - Peter van der Sleen
- Forest Ecology & Forest Management GroupWageningen UniversityWageningenThe Netherlands
- Wildlife Ecology and Conservation GroupWageningen UniversityWageningenThe Netherlands
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Francon L, Corona C, Till-Bottraud I, Carlson BZ, Stoffel M. Some (do not) like it hot: shrub growth is hampered by heat and drought at the alpine treeline in recent decades. Am J Bot 2020; 107:607-617. [PMID: 32239494 DOI: 10.1002/ajb2.1459] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 01/30/2020] [Indexed: 05/23/2023]
Abstract
PREMISE Mountain ecosystems are particularly sensitive to climate change. However, only a very small number of studies exist so far using annually resolved records of alpine plant growth spanning the past century. Here we aimed to identify the effects of heat waves and drought, driven by global warming, on annual radial growth of Rhododendron ferrugineum. METHODS We constructed two century-long shrub ring-width chronologies from R. ferrugineum individuals on two adjacent, north- and west-facing slopes in the southern French Alps. We analyzed available meteorological data (temperature, precipitation and drought) over the period 1960-2016. Climate-growth relationships were evaluated using bootstrapped correlation functions and structural equation models to identify the effects of rising temperature on shrub growth. RESULTS Analysis of meteorological variables during 1960-2016 revealed a shift in the late 1980s when heat waves and drought increased in intensity and frequency. In response to these extreme climate events, shrubs have experienced significant changes in their main limiting factors. Between 1960 and 1988, radial growth on both slopes was strongly controlled by the sum of growing degree days during the snow free period. Between 1989 and 2016, August temperature and drought have emerged as the most important. CONCLUSIONS Increasing air temperatures have caused a shift in the growth response of shrubs to climate. The recently observed negative effect of high summer temperature and drought on shrub growth can, however, be buffered by topographic variability, supporting the macro- and microrefugia hypotheses.
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Affiliation(s)
- Loïc Francon
- Université Clermont Auvergne, CNRS, GEOLAB, F-63000, Clermont-Ferrand, France
| | - Christophe Corona
- Université Clermont Auvergne, CNRS, GEOLAB, F-63000, Clermont-Ferrand, France
| | - Irène Till-Bottraud
- Université Clermont Auvergne, CNRS, GEOLAB, F-63000, Clermont-Ferrand, France
| | - Bradley Z Carlson
- Centre de Recherches sur les Ecosystèmes d'Altitude (CREA), Observatoire du Mont-Blanc, 74400, Chamonix, France
| | - Markus Stoffel
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland
- Department of Earth Sciences, University of Geneva, Geneva, Switzerland
- Department F.-A. Forel for Environmental and Aquatic Sciences, University of Geneva, Geneva, Switzerland
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Caetano-Andrade VL, Clement CR, Weigel D, Trumbore S, Boivin N, Schöngart J, Roberts P. Tropical Trees as Time Capsules of Anthropogenic Activity. Trends Plant Sci 2020; 25:369-380. [PMID: 32037081 DOI: 10.1016/j.tplants.2019.12.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 12/03/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
After the ice caps, tropical forests are globally the most threatened terrestrial environments. Modern trees are not just witnesses to growing contemporary threats but also legacies of past human activity. Here, we review the use of dendrochronology, radiocarbon analysis, stable isotope analysis, and DNA analysis to examine ancient tree management. These methods exploit the fact that living trees record information on environmental and anthropogenic selective forces during their own and past generations of growth, making trees living archaeological 'sites'. The applicability of these methods across prehistoric, historic, and industrial periods means they have the potential to detect evolving anthropogenic threats and can be used to set conservation priorities in rapidly vanishing environments.
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Affiliation(s)
| | | | - Detlef Weigel
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Susan Trumbore
- Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Nicole Boivin
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany; Department of Archaeology, University of Queensland, St Lucia QLD, 4072, Brisbane, Australia
| | - Jochen Schöngart
- Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, Brazil
| | - Patrick Roberts
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany; Department of Archaeology, University of Queensland, St Lucia QLD, 4072, Brisbane, Australia
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Vitasse Y, Bottero A, Cailleret M, Bigler C, Fonti P, Gessler A, Lévesque M, Rohner B, Weber P, Rigling A, Wohlgemuth T. Contrasting resistance and resilience to extreme drought and late spring frost in five major European tree species. Glob Chang Biol 2019; 25:3781-3792. [PMID: 31436853 DOI: 10.1111/gcb.14803] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 07/04/2019] [Accepted: 08/01/2019] [Indexed: 05/23/2023]
Abstract
Extreme climate events (ECEs) such as severe droughts, heat waves, and late spring frosts are rare but exert a paramount role in shaping tree species distributions. The frequency of such ECEs is expected to increase with climate warming, threatening the sustainability of temperate forests. Here, we analyzed 2,844 tree-ring width series of five dominant European tree species from 104 Swiss sites ranging from 400 to 2,200 m a.s.l. for the period 1930-2016. We found that (a) the broadleaved oak and beech are sensitive to late frosts that strongly reduce current year growth; however, tree growth is highly resilient and fully recovers within 2 years; (b) radial growth of the conifers larch and spruce is strongly and enduringly reduced by spring droughts-these species are the least resistant and resilient to droughts; (c) oak, silver fir, and to a lower extent beech, show higher resistance and resilience to spring droughts and seem therefore better adapted to the future climate. Our results allow a robust comparison of the tree growth responses to drought and spring frost across large climatic gradients and provide striking evidence that the growth of some of the most abundant and economically important European tree species will be increasingly limited by climate warming. These results could serve for supporting species selection to maintain the sustainability of forest ecosystem services under the expected increase in ECEs.
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Affiliation(s)
- Yann Vitasse
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
| | - Alessandra Bottero
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
| | - Maxime Cailleret
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
- UMR RECOVER, Aix Marseille Univ, IRSTEA, Aix-en-Provence, France
| | - Christof Bigler
- SwissForestLab, Birmensdorf, Switzerland
- Forest Ecology, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Patrick Fonti
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
| | - Arthur Gessler
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
- Institute of Terrestrial Ecology, ETH Zürich, Zürich, Switzerland
| | - Mathieu Lévesque
- SwissForestLab, Birmensdorf, Switzerland
- Forest Ecology, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Brigitte Rohner
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
| | - Pascale Weber
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
| | - Andreas Rigling
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
- Institute of Terrestrial Ecology, ETH Zürich, Zürich, Switzerland
| | - Thomas Wohlgemuth
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- SwissForestLab, Birmensdorf, Switzerland
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Lee Molinari R, Bishop TBB, Bekker MF, Kitchen SG, Allphin L, St. Clair SB. Creosote growth rate and reproduction increase in postfire environments. Ecol Evol 2019; 9:12897-12905. [PMID: 31788223 PMCID: PMC6875574 DOI: 10.1002/ece3.5771] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/06/2019] [Accepted: 09/17/2019] [Indexed: 11/07/2022] Open
Abstract
Human activities are changing patterns of ecological disturbance globally. In North American deserts, wildfire is increasing in size and frequency due to fuel characteristics of invasive annual grasses. Fire reduces the abundance and cover of native vegetation in desert ecosystems. In this study, we sought to characterize stem growth and reproductive output of a dominant native shrub in the Mojave Desert, creosote bush (Larrea tridentata (DC.) Coville) following wildfires that occurred in 2005. We sampled 55 shrubs along burned and unburned transects 12 years after the fires (2017) and quantified age, stem diameter, stem number, radial and vertical growth rates, and fruit production for each shrub. The shrubs on the burn transects were most likely postfire resprouts based on stem age while stems from unburn transects dated from before the fire. Stem and vertical growth rates for shrubs on burned transects were 2.6 and 1.7 times higher than that observed for shrubs on unburned transects. Fruit production of shrubs along burned transects was 4.7-fold more than shrubs along paired unburned transects. Growth rates and fruit production of shrubs in burned areas did not differ with increasing distance from the burn perimeter. Positive growth and reproduction responses of creosote following wildfires could be critical for soil stabilization and re-establishment of native plant communities in this desert system. Additional research is needed to assess if repeat fires that are characteristic of invasive grass-fire cycles may limit these benefits.
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Affiliation(s)
| | - Tara B. B. Bishop
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUtah
| | | | - Stanley G. Kitchen
- United States Department of Agriculture, Forest ServiceRocky Mountain Research StationProvoUtah
| | - Loreen Allphin
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUtah
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Wernicke J, Stark G, Wang L, Grießinger J, Bräuning A. Air moisture signals in a stable oxygen isotope chronology of dwarf shrubs from the central Tibetan Plateau. Ann Bot 2019; 124:53-64. [PMID: 31329817 PMCID: PMC6676389 DOI: 10.1093/aob/mcz030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/12/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Annually resolved biological climate proxies beyond the altitudinal and latitudinal distribution limit of trees are rare. In such regions, several studies have demonstrated that annual growth rings of dwarf shrubs are suitable proxies for palaeoclimatic investigations. In High Asia, the pioneer work of Liang et al. (Liang E, Lu X, Ren P, Li X, Zhu L, Eckstein D, 2012. Annual increments of juniper dwarf shrubs above the tree line on the central Tibetan Plateau: a useful climatic proxy. Annals of Botany109: 721-728) confirmed the suitability of shrub growth-ring chronologies for palaeoclimatic research. This study presents the first sensitivity study of an annually resolved δ18O time series inferred from Wilson juniper (Juniperus pingii var. wilsonii) from the northern shoreline of lake Nam Co (Tibetan Plateau). METHODS Based on five individual dwarf shrub discs, a statistically reliable δ18O chronology covering the period 1957-2009 was achieved (expressed population signal = 0.80). Spearman's correlation analysis between the δ18O chronology and climate variables from different sources was applied. In a first step, the suitability of various climate data was evaluated. KEY RESULTS Examinations of climate-proxy relationships revealed significant negative correlations between the δ18O shrub chronology and summer season moisture variability of the previous and current year. In particular, relative humidity of the previous and current vegetation period significantly determined the proxy variability (ρ = -0.48, P < 0.01). Furthermore, the δ18O variability of the developed shrub chronology significantly coincided with a nearby tree-ring δ18O chronology of the same genus (r = 0.62, P < 0.01). CONCLUSIONS The δ18O shrub chronology reliably recorded humidity variations in the Nam Co region. The chronology was significantly correlated with a nearby moisture-sensitive tree-ring δ18O chronology, indicating a common climate signal in the two chronologies. This climate signal was likely determined by moisture variations of the Asian summer monsoon. Local climate effects were superimposed on the supra-regional climate signature of the monsoon circulation. Opposing δ18O values between the two chronologies were interpreted as plant-physiological differences during isotopic fractionation processes.
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Affiliation(s)
- Jakob Wernicke
- Institute of Geography, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Georg Stark
- Institute of Geography, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Lily Wang
- Institute of Geographical Sciences and Natural Resource Research, Chinese Academy of Sciences, Beijing, China
| | - Jussi Grießinger
- Institute of Geography, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Achim Bräuning
- Institute of Geography, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
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38
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Helcoski R, Tepley AJ, Pederson N, McGarvey JC, Meakem V, Herrmann V, Thompson JR, Anderson-Teixeira KJ. Growing season moisture drives interannual variation in woody productivity of a temperate deciduous forest. New Phytol 2019; 223:1204-1216. [PMID: 31077588 DOI: 10.1111/nph.15906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
The climate sensitivity of forest ecosystem woody productivity (ANPPstem ) influences carbon cycle responses to climate change. For the first time, we combined long-term annual growth and forest census data of a diverse temperate broadleaf deciduous forest, seeking to resolve whether ANPPstem is primarily moisture- or energy-limited and whether climate sensitivity has changed in recent decades characterised by more mesic conditions and elevated CO2 . We analysed tree-ring chronologies across 109 yr of monthly climatic variation (1901-2009) for 14 species representing 97% of ANPPstem in a 25.6 ha plot in northern Virginia, USA. Radial growth of most species and ecosystem-level ANPPstem responded positively to cool, moist growing season conditions, but the same conditions in the previous May-July were associated with reduced growth. In recent decades (1980-2009), responses were more variable and, on average, weaker. Our results indicated that woody productivity is primarily limited by current growing season moisture, as opposed to temperature or sunlight, but additional complexity in climate sensitivity may reflect the use of stored carbohydrate reserves. Overall, while such forests currently display limited moisture sensitivity, their woody productivity is likely to decline under projected hotter and potentially drier growing season conditions.
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Affiliation(s)
- Ryan Helcoski
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Alan J Tepley
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
- W. A. Franke College of Forestry & Conservation, University of Montana, Missoula, MT, 59812, USA
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | | | - Jennifer C McGarvey
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Victoria Meakem
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Valentine Herrmann
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Jonathan R Thompson
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
- Harvard Forest, Petersham, MA, 01366, USA
| | - Kristina J Anderson-Teixeira
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, 22630, USA
- Center for Tropical Forest Science-Forest Global Earth Observatory, Smithsonian Tropical Research Institute, Panama City, Panama
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Tumajer J, Treml V. Disentangling the effects of disturbance, climate and tree age on xylem hydraulic conductivity of Betula pendula. Ann Bot 2019; 123:783-792. [PMID: 30551134 PMCID: PMC6526315 DOI: 10.1093/aob/mcy209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND AIMS The increasing frequency of disturbances in temperate forests is responsible for the greater numbers of trees with mechanically damaged cambial zones. Adjustment of wood anatomical structure to balance between safe and efficient water conductivity is one mechanism trees employ to cope with mechanical damage. The relative role of disturbances, tree age and climate in shaping xylem conduits and affecting xylem hydraulic conductivity remains unknown. METHODS We performed an experiment with five different mechanical treatments simulating natural disturbances of juvenile Betula pendula trees (stem scarring, tilting, decapitation, root exposure and stem-base burial). After 3 years, trees were cut down, conduit size and density were measured, and specific hydraulic conductivity of each tree ring was calculated. Between-tree and between-year variability in xylem conductivity was decomposed into effects of tree age, climate and disturbances using linear mixed-effects models. KEY RESULTS Xylem-specific hydraulic conductivity decreased significantly after treatment in decapitated, tilted and scarred trees. In the last treatment, wood anatomical adjustment was restricted to the area next to the callus tissue zone; in contrast, specific hydraulic conductivity declined over the entire stem circumference after tilting or decapitation. The response of trees with buried stems and exposed roots was generally weak. The overall effect of disturbances on inter-annual variability of wood anatomical structure was greater than the contribution of tree age and climate. CONCLUSIONS The results indicate that disturbances are important drivers of xylem hydraulic conductivity. Expected increases in the frequency and intensity of disturbances may alter the theoretical capacity of forest stands for water conductance with a feedback to climate.
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Affiliation(s)
- Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
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Black BA, Andersson C, Butler PG, Carroll ML, DeLong KL, Reynolds DJ, Schöne BR, Scourse J, van der Sleen P, Wanamaker AD, Witbaard R. The revolution of crossdating in marine palaeoecology and palaeoclimatology. Biol Lett 2019; 15:20180665. [PMID: 30958223 DOI: 10.1098/rsbl.2018.0665] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Over the past century, the dendrochronology technique of crossdating has been widely used to generate a global network of tree-ring chronologies that serves as a leading indicator of environmental variability and change. Only recently, however, has this same approach been applied to growth increments in calcified structures of bivalves, fish and corals in the world's oceans. As in trees, these crossdated marine chronologies are well replicated, annually resolved and absolutely dated, providing uninterrupted multi-decadal to millennial histories of ocean palaeoclimatic and palaeoecological processes. Moreover, they span an extensive geographical range, multiple trophic levels, habitats and functional types, and can be readily integrated with observational physical or biological records. Increment width is the most commonly measured parameter and reflects growth or productivity, though isotopic and elemental composition capture complementary aspects of environmental variability. As such, crossdated marine chronologies constitute powerful observational templates to establish climate-biology relationships, test hypotheses of ecosystem functioning, conduct multi-proxy reconstructions, provide constraints for numerical climate models, and evaluate the precise timing and nature of ocean-atmosphere interactions. These 'present-past-future' perspectives provide new insights into the mechanisms and feedbacks between the atmosphere and marine systems while providing indicators relevant to ecosystem-based approaches of fisheries management.
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Affiliation(s)
- Bryan A Black
- 1 Laboratory of Tree-Ring Research, University of Arizona , 1215 E Lowell St, Tucson, AZ 85721 , USA
| | - Carin Andersson
- 2 NORCE Norwegian Research Centre, Bjerknes Centre for Climate Research , Jahnebakken 5, 5007 Bergen , Norway
| | - Paul G Butler
- 3 CGES, College of Life and Environmental Sciences, University of Exeter , Penryn Campus, Treliever Road, Penryn, Cornwall TR10 9EZ , UK
| | - Michael L Carroll
- 4 Akvaplan-niva AS, Fram - High North Research Centre for Climate and the Environment , PO Box 6606 Langnes, 9296 Tromsø , Norway
| | - Kristine L DeLong
- 5 Department of Geography & Anthropology and the Coastal Studies institute, Louisiana State University , 227 Howe-Russell Geoscience Complex E326, Baton Rouge, LA 70803 , USA
| | - David J Reynolds
- 6 School of Earth and Ocean Sciences, Cardiff University , Cardiff CF10 3AT , UK
| | - Bernd R Schöne
- 7 Institute of Geosciences, University of Mainz , Johann-Joachim-Becher-Weg 21, 55128 Mainz , Germany
| | - James Scourse
- 8 CGES, College of Life and Environmental Sciences, University of Exeter , Penryn Campus, Treliever Road, Penryn, Cornwall TR10 9EZ , UK
| | - Peter van der Sleen
- 9 Department of Wetland Ecology, Karlsruhe Institute of Technology , Josefstrasse 1, Rastatt 76437 , Germany
| | - Alan D Wanamaker
- 10 Department of Geological and Atmospheric Sciences, Iowa State University , 2237 Osborn Drive, Ames, IA 50011 , USA
| | - Rob Witbaard
- 11 Department of Estuarine and Delta Systems, Royal Netherlands Institute for Sea Research (NIOZ) , PO Box 140, 4400 AC Yerseke , the Netherlands
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Yi K, Maxwell JT, Wenzel MK, Roman DT, Sauer PE, Phillips RP, Novick KA. Linking variation in intrinsic water-use efficiency to isohydricity: a comparison at multiple spatiotemporal scales. New Phytol 2019; 221:195-208. [PMID: 30117538 DOI: 10.1111/nph.15384] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
Species-specific responses of plant intrinsic water-use efficiency (iWUE) to multiple environmental drivers associated with climate change, including soil moisture (θ), vapor pressure deficit (D), and atmospheric CO2 concentration (ca ), are poorly understood. We assessed how the iWUE and growth of several species of deciduous trees that span a gradient of isohydric to anisohydric water-use strategies respond to key environmental drivers (θ, D and ca ). iWUE was calculated for individual tree species using leaf-level gas exchange and tree-ring δ13 C in wood measurements, and for the whole forest using the eddy covariance method. The iWUE of the isohydric species was generally more sensitive to environmental change than the anisohydric species was, and increased significantly with rising D during the periods of water stress. At longer timescales, the influence of ca was pronounced for isohydric tulip poplar but not for others. Trees' physiological responses to changing environmental drivers can be interpreted differently depending on the observational scale. Care should be also taken in interpreting observed or modeled trends in iWUE that do not explicitly account for the influence of D.
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Affiliation(s)
- Koong Yi
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
| | - Justin T Maxwell
- Department of Geography, Indiana University Bloomington, 701 East Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Matthew K Wenzel
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
| | - D Tyler Roman
- US Department of Agriculture Forest Service, Northern Research Station, 1831 Highway 169 East, Grand Rapids, MN, 55744, USA
| | - Peter E Sauer
- Department of Geological Science, Indiana University Bloomington, 1001 East Tenth Street, Bloomington, IN, 47405, USA
| | - Richard P Phillips
- Department of Biology, Indiana University Bloomington, 1001 East Third Street, Bloomington, IN, 47405, USA
| | - Kimberly A Novick
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
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42
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Altman J, Ukhvatkina ON, Omelko AM, Macek M, Plener T, Pejcha V, Cerny T, Petrik P, Srutek M, Song JS, Zhmerenetsky AA, Vozmishcheva AS, Krestov PV, Petrenko TY, Treydte K, Dolezal J. Poleward migration of the destructive effects of tropical cyclones during the 20th century. Proc Natl Acad Sci U S A 2018; 115:11543-8. [PMID: 30348774 DOI: 10.1073/pnas.1808979115] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Determination of long-term tropical cyclone (TC) variability is of enormous importance to society; however, changes in TC activity are poorly understood owing to discrepancies among various datasets and limited span of instrumental records. While the increasing intensity and frequency of TCs have been previously documented on a long-term scale using various proxy records, determination of their poleward migration has been based mostly on short-term instrumental data. Here we present a unique tree-ring-based approach for determination of long-term variability in TC activity via forest disturbance rates in northeast Asia (33-45°N). Our results indicate significant long-term changes in TC activity, with increased rates of disturbances in the northern latitudes over the past century. The disturbance frequency was stable over time in the southern latitudes, however. Our findings of increasing disturbance frequency in the areas formerly situated at the edge of TC activity provide evidence supporting the broad relevance of poleward migration of TCs. Our results significantly enhance our understanding of the effects of climate change on TCs and emphasize the need for determination of long-term variation of past TC activity to improve future TC projections.
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43
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van Mantgem PJ, Falk DA, Williams EC, Das AJ, Stephenson NL. Pre-fire drought and competition mediate post-fire conifer mortality in western U.S. National Parks. Ecol Appl 2018; 28:1730-1739. [PMID: 30151923 DOI: 10.1002/eap.1778] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 04/05/2018] [Accepted: 05/10/2018] [Indexed: 06/08/2023]
Abstract
Tree mortality is an important outcome of many forest fires. Extensive tree injuries from fire may lead directly to mortality, but environmental and biological stressors may also contribute to tree death. However, there is little evidence showing how the combined effects of two common stressors, drought and competition, influence post-fire mortality. Geographically broad observations of three common western coniferous trees subjected to prescribed fire showed the likelihood of post-fire mortality was related to intermediate-term (10 yr) pre-fire average radial growth, an important component of tree vigor. Path analysis showed that indices of competition and drought stress prior to fire can be described in terms of joint effects on growth, indirectly affecting post-fire mortality. Our results suggest that the conditions that govern the relationship between growth and mortality in unburned stands may also apply to post-fire environments. Thus, biotic and abiotic changes that affect growth negatively (e.g., drought stress) or positively (e.g., growth releases following thinning treatments) prior to fire may influence expressed fire severity, independent of fire intensity (e.g., heat flux, residence time). These relationships suggest that tree mortality may increase under stressful climatic or stand conditions even if fire behavior remains constant.
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Affiliation(s)
- Phillip J van Mantgem
- Western Ecological Research Center, U.S. Geological Survey, Arcata, California, 95521, USA
| | - Donald A Falk
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, 85721, USA
| | - Emma C Williams
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, 85721, USA
| | - Adrian J Das
- Western Ecological Research Center, U.S. Geological Survey, Three Rivers, California, 93271, USA
| | - Nathan L Stephenson
- Western Ecological Research Center, U.S. Geological Survey, Three Rivers, California, 93271, USA
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44
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Manzanedo RD, Ballesteros‐Cánovas J, Schenk F, Stoffel M, Fischer M, Allan E. Increase in CO 2 concentration could alter the response of Hedera helix to climate change. Ecol Evol 2018; 8:8598-8606. [PMID: 30250726 PMCID: PMC6144985 DOI: 10.1002/ece3.4388] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 05/25/2018] [Accepted: 06/17/2018] [Indexed: 11/22/2022] Open
Abstract
Increasing CO 2 concentration ([CO 2]) is likely to affect future species distributions, in interaction with other climate change drivers. However, current modeling approaches still seldom consider interactions between climatic factors and the importance of these interactions therefore remains mostly unexplored. Here, we combined dendrochronological and modeling approaches to study the interactive effects of increasing [CO 2] and temperature on the distribution of one of the main European liana species, Hedera helix. We combined a classical continent-wide species distribution modeling approach with a case study using H. helix and Quercus cerris tree rings, where we explored the long-term influence of a variety of climate drivers, including increasing [CO 2], and their interactions, on secondary growth. Finally, we explored how our findings could influence the model predictions. Climate-only model predictions showed a small decrease in habitat suitability for H. helix in Europe; however, this was accompanied by a strong shift in the distribution toward the north and east. Our growth ring data suggested that H. helix can benefit from high [CO 2] under warm conditions, more than its tree hosts, which showed a weaker response to [CO 2] coupled with higher cavitation risk under high temperature. Increasing [CO 2] might therefore offset the negative effects of high temperatures on H. helix, and we illustrate how this might translate into maintenance of H. helix in warmer areas. Our results highlight the need to consider carbon fertilization and interactions between climate variables in ecological modeling. Combining dendrochronological analyses with spatial distribution modeling may provide opportunities to refine predictions of how climate change will affect species distributions.
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Affiliation(s)
| | - Juan Ballesteros‐Cánovas
- dendrolab.chInstitute of Geological SciencesUniversity of BernBernSwitzerland
- Climatic Change and Climate ImpactsInstitute for Environmental SciencesUniversity of GenevaGenevaSwitzerland
| | - Floris Schenk
- Institute of Plant SciencesUniversity of BernBernSwitzerland
| | - Markus Stoffel
- dendrolab.chInstitute of Geological SciencesUniversity of BernBernSwitzerland
- Climatic Change and Climate ImpactsInstitute for Environmental SciencesUniversity of GenevaGenevaSwitzerland
- Department of Earth SciencesUniversity of GenevaGenevaSwitzerland
| | - Markus Fischer
- Institute of Plant SciencesUniversity of BernBernSwitzerland
| | - Eric Allan
- Institute of Plant SciencesUniversity of BernBernSwitzerland
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45
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Zhang Y, Yin DC, Tian K, He RH, He MZ, Li YC, Sun DC, Zhang WG. [Relationship between radial growth of Abies georgei and climate factors at different altitudes on the eastern slope of Yulong Snow Mountain, China.]. Ying Yong Sheng Tai Xue Bao 2018; 29:2355-2361. [PMID: 30039675 DOI: 10.13287/j.1001-9332.201807.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Based on dendrochronological methods, we established residual chronologies (RES) of Abies georgei at low, middle and high altitudes with ring width data on the eastern slope of Yulong Snow Mountain. We examined the relationship between the radial growth and climate factors (temperature and precipitation) by response function analysis and redundancy analysis (RDA) to identify the key climatic factors driving the radial growth of A. georgei. The results showed that the responses of radial growth of A. georgei to climates were consistent at three altitudes, which was jointly controlled by temperature and precipitation. This consistency was related to the steep terrain of Yulong Snow Mountain, the high-altitude distribution, and shallow root characteristics of A. georgei. At all three altitudes, tree growth showed significantly positive correlation with mean temperature of the current July, mean temperature of the previous November, and precipitation of the current January, but negative correlation with precipitation of the current June. The comprehensive application of response function analysis and redundancy analysis could accurately reveal the relationship between tree growth and climatic factors along environmental gradients. Our results provided a scientific basis for climatic reconstruction and forest management in the area.
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Affiliation(s)
- Yun Zhang
- College of Wetlands/National Plateau Wetlands Research Center, Southwest Forestry University, Kunming 650224, China.,Naitional Positioning Research Station for Dianchi Wetland Ecosystem, Kunming 650224, China
| | - Ding Cai Yin
- College of Wetlands/National Plateau Wetlands Research Center, Southwest Forestry University, Kunming 650224, China.,School of Geography, Southwest Forestry University, Kunming 650224, China
| | - Kun Tian
- College of Wetlands/National Plateau Wetlands Research Center, Southwest Forestry University, Kunming 650224, China.,Naitional Positioning Research Station for Dianchi Wetland Ecosystem, Kunming 650224, China
| | - Rong Hua He
- Administration of Yulong Snow Mountain Provincial Nature Reserve, Lijiang 674100, Yunnan, China
| | - Mao Zhen He
- Administration of Yulong Snow Mountain Provincial Nature Reserve, Lijiang 674100, Yunnan, China
| | - Yu Chun Li
- Administration of Yulong Snow Mountain Provincial Nature Reserve, Lijiang 674100, Yunnan, China
| | - Da Cheng Sun
- College of Wetlands/National Plateau Wetlands Research Center, Southwest Forestry University, Kunming 650224, China
| | - Wei Guo Zhang
- College of Wetlands/National Plateau Wetlands Research Center, Southwest Forestry University, Kunming 650224, China.,School of Geography, Southwest Forestry University, Kunming 650224, China
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46
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Jia HF, Mou YM, Danzeng LB, Li Y. [Age investigation and growth history analysis of old trees in Nyemo County of Tibet, China.]. Ying Yong Sheng Tai Xue Bao 2018; 29:2401-2410. [PMID: 30039680 DOI: 10.13287/j.1001-9332.201807.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Investigating age and growth histories of old trees is important for census and document of old trees in China. In this study, we analyzed the age and growth histories of 20 old trees of Juglans regia and 10 old trees of Sabina tibeticain Nyemo County, Tibet, China, using dendrochronological methods. The results showed that 4, 7 and 9 J. regia trees were identified as Class 1, 2 and 3 to protection, and 2, 4 and 4 S. tibetica trees as Class 1, 2 and 3 to protection, respectively. Tree growth of both species was synchronized in the study area, especially during 1940s-1980s. There were substantial differences in the growth among individuals. Significantly positive correlation was found between the ring-width chronologies of the two tree species and Palmer drought severity indices (PDSI). Old trees were mainly distributed in villages and road sides, where human activities were frequent. In addition to the climatic factors, frequent human activities in the study area played an important role in affecting tree radial growth. It caused synchronous radial growth of the old trees between those two species and significant variation among different individuals. Both climate change and human activities should be considered to make the conservation plans for old trees in Nyemo County.
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Affiliation(s)
- Heng Feng Jia
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Mei Mou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | | | - Yan Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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47
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Tao J, He D, Kennard MJ, Ding C, Bunn SE, Liu C, Jia Y, Che R, Chen Y. Strong evidence for changing fish reproductive phenology under climate warming on the Tibetan Plateau. Glob Chang Biol 2018; 24:2093-2104. [PMID: 29331066 DOI: 10.1111/gcb.14050] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 12/17/2017] [Accepted: 12/22/2017] [Indexed: 05/26/2023]
Abstract
Phenological responses to climate change have been widely observed and have profound and lasting effects on ecosystems and biodiversity. However, compared to terrestrial ecosystems, the long-term effects of climate change on species' phenology are poorly understood in aquatic ecosystems. Understanding the long-term changes in fish reproductive phenology is essential for predicting population dynamics and for informing management strategies, but is currently hampered by the requirement for intensive field observations and larval identification. In this study, a very low-frequency sampling of juveniles and adults combined with otolith measurements (long axis length of the first annulus; LAFA) of an endemic Tibetan Plateau fish (Gymnocypris selincuoensis) was used to examine changes in reproductive phenology associated with climate changes from the 1970s to 2000s. Assigning individual fish to their appropriate calendar year class was assisted by dendrochronological methods (crossdating). The results demonstrated that LAFA was significantly and positively associated with temperature and growing season length. To separate the effects of temperature and the growing season length on LAFA growth, measurements of larval otoliths from different sites were conducted and revealed that daily increment additions were the main contributor (46.3%), while temperature contributed less (12.0%). Using constructed water-air temperature relationships and historical air temperature records, we found that the reproductive phenology of G. selincuoensis was strongly advanced in the spring during the 1970s and 1990s, while the increased growing season length in the 2000s was mainly due to a delayed onset of winter. The reproductive phenology of G. selincuoensis advanced 2.9 days per decade on average from the 1970s to 2000s, and may have effects on recruitment success and population dynamics of this species and other biota in the ecosystem via the food web. The methods used in this study are applicable for studying reproductive phenological changes across a wide range of species and ecosystems.
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Affiliation(s)
- Juan Tao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
- Australian Rivers Institute, Griffith University, Brisbane, Qld, Australia
| | - Dekui He
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Mengla, China
| | - Mark J Kennard
- Australian Rivers Institute, Griffith University, Brisbane, Qld, Australia
| | - Chengzhi Ding
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Yunnan University, Kunming, China
| | - Stuart E Bunn
- Australian Rivers Institute, Griffith University, Brisbane, Qld, Australia
| | - Chunlong Liu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yintao Jia
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Rongxiao Che
- Environmental Futures Research Institute, Griffith University, Brisbane, Qld, Australia
| | - Yifeng Chen
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Australian Rivers Institute, Griffith University, Brisbane, Qld, Australia
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48
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Cahoon SMP, Sullivan PF, Brownlee AH, Pattison RR, Andersen HE, Legner K, Hollingsworth TN. Contrasting drivers and trends of coniferous and deciduous tree growth in interior Alaska. Ecology 2018; 99:1284-1295. [PMID: 29569245 DOI: 10.1002/ecy.2223] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 01/19/2018] [Accepted: 03/02/2018] [Indexed: 11/09/2022]
Abstract
The boreal biome represents approximately one third of the world's forested area and plays an important role in global biogeochemical and energy cycles. Numerous studies in boreal Alaska have concluded that growth of black and white spruce is declining as a result of temperature-induced drought stress. The combined evidence of declining spruce growth and changes in the fire regime that favor establishment of deciduous tree species has led some investigators to suggest the region may be transitioning from dominance by spruce to dominance by deciduous forests and/or grasslands. Although spruce growth trends have been extensively investigated, few studies have evaluated long-term radial growth trends of the dominant deciduous species (Alaska paper birch and trembling aspen) and their sensitivity to moisture availability. We used a large and spatially extensive sample of tree cores from interior Alaska to compare long-term growth trends among contrasting tree species (white and black spruce vs. birch and aspen). All species showed a growth peak in the mid-1940s, although growth following the peak varied strongly across species. Following an initial decline from the peak, growth of white spruce showed little evidence of a trend, while black spruce and birch growth showed slight growth declines from ~1970 to present. Aspen growth was much more variable than the other species and showed a steep decline from ~1970 to present. Growth of birch, black and white spruce was sensitive to moisture availability throughout most of the tree-ring chronologies, as evidenced by negative correlations with air temperature and positive correlations with precipitation. However, a positive correlation between previous July precipitation and aspen growth disappeared in recent decades, corresponding with a rise in the population of the aspen leaf miner (Phyllocnistis populiella), an herbivorous moth, which may have driven growth to a level not seen since the early 20th century. Our results provide important historical context for recent growth and raise questions regarding competitive interactions among the dominant tree species and exchanges of carbon and energy in the warming climate of interior Alaska.
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Affiliation(s)
- Sean M P Cahoon
- Environment and Natural Resources Institute, University of Alaska Anchorage, Anchorage, Alaska, 99508, USA
| | - Patrick F Sullivan
- Environment and Natural Resources Institute, University of Alaska Anchorage, Anchorage, Alaska, 99508, USA
| | - Annalis H Brownlee
- Environment and Natural Resources Institute, University of Alaska Anchorage, Anchorage, Alaska, 99508, USA
| | - Robert R Pattison
- Pacific Northwest Research Station, USDA Forest Service, Anchorage, Alaska, 99501, USA
| | - Hans-Erik Andersen
- Pacific Northwest Research Station, USDA Forest Service, Seattle, Washington, 98195, USA
| | - Kate Legner
- Pacific Northwest Research Station, USDA Forest Service, Anchorage, Alaska, 99501, USA
| | - Teresa N Hollingsworth
- Boreal Ecology Cooperative Research Unit, USDA Forest Service, Fairbanks, Alaska, 99775, USA
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49
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Abstract
The techniques of dendrochronology (tree-ring dating) and radiocarbon (14C) dating are described, as they are applied to historic buildings. Both rely on determining the felling dates of the trees used in their construction. For dendrochronology, the construction of master chronologies and the matching of individual ring-width sequences to them is described and, for radiocarbon dating, the use of tree-ring results in calibration. Results of dating are discussed, ranging from the cathedrals of Peterborough and Beauvais and the development of crown-post roof structures, to the dating and identification of standing medieval peasant houses, particularly those built using cruck construction.
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50
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Weijers S, Buchwal A, Blok D, Löffler J, Elberling B. High Arctic summer warming tracked by increased Cassiope tetragona growth in the world's northernmost polar desert. Glob Chang Biol 2017; 23:5006-5020. [PMID: 28464494 DOI: 10.1111/gcb.13747] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 04/18/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
Rapid climate warming has resulted in shrub expansion, mainly of erect deciduous shrubs in the Low Arctic, but the more extreme, sparsely vegetated, cold and dry High Arctic is generally considered to remain resistant to such shrub expansion in the next decades. Dwarf shrub dendrochronology may reveal climatological causes of past changes in growth, but is hindered at many High Arctic sites by short and fragmented instrumental climate records. Moreover, only few High Arctic shrub chronologies cover the recent decade of substantial warming. This study investigated the climatic causes of growth variability of the evergreen dwarf shrub Cassiope tetragona between 1927 and 2012 in the northernmost polar desert at 83°N in North Greenland. We analysed climate-growth relationships over the period with available instrumental data (1950-2012) between a 102-year-long C. tetragona shoot length chronology and instrumental climate records from the three nearest meteorological stations, gridded climate data, and North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) indices. July extreme maximum temperatures (JulTemx ), as measured at Alert, Canada, June NAO, and previous October AO, together explained 41% of the observed variance in annual C. tetragona growth and likely represent in situ summer temperatures. JulTemx explained 27% and was reconstructed back to 1927. The reconstruction showed relatively high growing season temperatures in the early to mid-twentieth century, as well as warming in recent decades. The rapid growth increase in C. tetragona shrubs in response to recent High Arctic summer warming shows that recent and future warming might promote an expansion of this evergreen dwarf shrub, mainly through densification of existing shrub patches, at High Arctic sites with sufficient winter snow cover and ample water supply during summer from melting snow and ice as well as thawing permafrost, contrasting earlier notions of limited shrub growth sensitivity to summer warming in the High Arctic.
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Affiliation(s)
- Stef Weijers
- Department of Geography, University of Bonn, Bonn, Germany
| | - Agata Buchwal
- Institute of Geoecology and Geoinformation, Adam Mickiewicz University, Poznan, Poland
- Department of Biological Sciences, Ecosystem and Biomedical Lab, University of Alaska Anchorage, Anchorage, AK, USA
| | - Daan Blok
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
| | - Jörg Löffler
- Department of Geography, University of Bonn, Bonn, Germany
| | - Bo Elberling
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
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